Are they really my parents?

Understanding the ABO blood types and Rh System

Are they really my parents? Blood types can offer some helpful information. Dr. Greene explains what you can and can not find out from blood types.

Dr. Greene’s Answer:

Genetics can be so confusing! I can easily see how after much research the issue about your parents would still appear murky.

Historical Background

The modern science of genetics had its start in 1866 when an Austrian monk named Gregor Mendel provided a simple yet powerful description of how traits are passed on from one generation to another. Mendel’s work was unappreciated until 1900 — more than fifteen years after his death. In his initial formulation, he described how sexual beings get two genes for each trait, one from each parent. The trait expressed, or visible, is a result of the interplay between these two genes. Specifically, he recognized that some genes are dominant and some are recessive. If you have one copy of a dominant gene you will express that trait, regardless of the other gene. In order to express a recessive trait you must have two recessive genes.

Mendel’s first experiments, though simple, were quite profound. He worked with peas, which had easily distinguishable traits, such as green versus yellow seeds. Each pea has two seed-color genes, one from each parent. The peas with two yellow genes were yellow. Those with a yellow and a green gene were also yellow; only those with two green genes turned out to be green. Thus yellow was dominant over the recessive green gene.

The Genetics of Human Blood

The situation with human blood genetics is far more complex, since at each point there are multiple possible characteristics. Nevertheless, the genetics of human blood is far better understood than that of any other human tissue. While there are rare exceptions, the following information on blood types applies to most people.

The ABO Blood Types

  • Each person receives an A, a B, or an O gene from each parent.
  • The A and B genes are co-dominant, and the O gene is recessive.
  • A person whose genetic type is either AA or AO will have blood type A, those with genetic type BB or BO will have blood type B, and only those with genetic type OO will have blood type O.
  • A child with type O blood can have parents with type A, type B, or type O blood, but not type AB. Conversely, if two parents both have type O blood, all their children will have type O blood.

The Rh System

Another medically important blood type is described in the Rh system. These genes were first discovered in the rhesus monkey, hence the designation Rh. The Rh system is actually far more complex than the ABO system in that there are 35 different possibilities that one could inherit from each parent. These, however, are roughly grouped into positive and negative types. In this system the positive are dominant over the negative.

  • If your genetic type is ++ or +-, your blood type will be Rh-positive.
  • Only if your genetic type is — will you be Rh negative.
  • If both parents have Rh+ blood with the +- genes, they could have children who are ++, +-, or –. In other words, their children could be either Rh positive or Rh negative.
  • Most children who are O negative have parents who are positive since the +- combination is so much more common than the — combination.

Two parents who have O positive blood could easily have a child who is O negative. In fact, most children who are O negative have parents who are positive, since the +- combination is so much more common than the — combination.

Non-ABO, Non-Rh Systems

As it turns out, there are more than a dozen complete blood group systems other than the ABO system and the Rh system. This makes great precision possible in looking at inheritance and family trees.

There is no reason, based on your blood type, to suspect that your parents might not really be your parents. If questions linger for other reasons, specific tests are available through blood banks and private laboratories that can settle the issue. These tests are commonly known as paternity and maternity DNA testing (for father and mother respectively). Given the billions of unique people on this planet, the power and precision of genetic testing are amazing.

Resources and References

Dean L. Blood Groups and Red Cell Antigens. Bethesda (MD): National Center for Biotechnology Information (US); 2005. Chapter 5, The ABO blood group.

 

Medical review by: Laura Webb, Khanh-Van Le-Bucklin
Last medical review: May 05, 2023
Updated: May 22, 2023

Dr. Greene is a practicing physician, author, national and international TEDx speaker, and global health advocate. He is a graduate of Princeton University and University of California San Francisco.

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1,338 Comments

Add a Comment
  1. Anthony

    Good Article. Your math is a little off in the beginning. The Australian started genetics in 1866 but was underappreciated until 1900 more than 50 years after his death? He would have had to publish and die no later than 1850 and then be appreciated for the work in 1900 for it to be 50 years after his death. Yet you state he started genetics in 1866?

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  2. MICHELLE

    Hello i was wondering if my child father is o postive and im 0 negative my son is A POSTIVE WHAT DOES THAT MEAN WOULD THAT BE HIS FATHER

    Added:
    • Cheryl Greene

      Hi Michelle,

      Our current understanding of genetics is that it is not possible for one parent to have O+ blood, the other parent to have O- blood and their child to have A+ blood. Two parents with type O blood can only have a child with type O blood.

      However, it’s not uncommon for blood types to be different than they are thought. As the next step, it is wise to have all your blood retested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
    • Penelope

      Why am i O- blood group and my fathers AB+ blood group and mother O-
      why why why, am i an alien?

      Added:
  3. Kofi

    I am O-{man} and my will to be partner is 0+. are we compactible to marry, with no consequences afterwards? I need you to explain what may happen if our child inherits my genes ,that is , O-.Thank you.

    Added:
    • Cheryl Greene

      Hello Kofi,

      Great question. Dr. Greene explains this in-depth in this article — How To Determine and Manage Rh Incompatibility.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  4. Tejaswini

    hi ,
    I have B+ve and my husband has 0+ve blood group , i gave birth to AB+ve Child.. kindly suggest how can my Son have AB+ve ?? i am scared.

    Added:
    • Cheryl Greene

      Hi Tejaswini,

      There is no need to fear, but it would be wise to have all your blood types retested. Likely one of them is different that you think it is. But if they all come back as you’ve reported, the next step is to have a DNA paternity test run.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  5. Porshia

    Can two parents have blood groups B+ and O+ and the child have AB+

    Added:
    • Cheryl Greene

      Hi Porshia,

      Thanks for writing in. Let me begin by saying that often blood types are different than they are thought to be.

      Our current understanding of genetics is that it is not possible for one parent to have type B+ blood, the other parent to have type O+ blood and their child to have type AB+ blood. If one parent has type B+ blood and the other has type O+ blood, each of their children could have blood type B+, or B-, or O+, or O-.

      Before you jump to any conclusions, it would be wise to have all your blood retested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  6. Ashley

    Can an AB positive and AB negative have an RH negative child?

    Added:
    • Cheryl Greene

      Hi Ashley,

      Yes, and AB+ parent and an AB- parent can have an Rh- child. In fact, there is a 25% chance each o their children will be Rh-.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  7. Muhammed

    Hi sir.
    My name is munsir .
    I have a question?
    My father and mother has o+ blood group
    But mine A+ how it possible?
    And are they really my parents ?

    Added:
    • Cheryl Greene

      Hi Muhammed,

      Our current understanding of genetics is that it is not possible for two parents to have type O+ blood and their child to have type A+ blood. But, it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  8. Sheema

    Hi Greene,
    My father was B+ and my mom is O+ my other two siblings are O+ and i am A+ . So is it possible for me to be their daughter?
    Thanks,

    Added:
    • Cheryl Greene

      Hi Sheema,

      Thanks for writing in. First, I need to tell you — often blood types are different than what they are thought to be. But if one parent has type B+ blood and if the other has type O+ blood they can have children who are either O+, O-, B+ or B-. They can not have a child with A+ blood. However if one parent has type A+ blood and the other has type O+ blood they could have children who are either O+, O-, A+ or A-.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  9. Amanda

    Helen if Mother is A+ andFather O_ is it possible that child is Rh+

    Added:
    • Cheryl Greene

      Hi Amanda,

      Great question. If one or two parents are Rh+ each of their children can be Rh+ or Rh-. If both parents are Rh- none of their children can be Rh+.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  10. Robyn

    Both parents are Blood type A, and my brother is 1 of 4 children and the only one with O+ blood. He’s been told that this is not possible. Help!

    Added:
    • Cheryl Greene

      Hi Robyn,

      Great question.

      It is possible for two parents with type A blood to have a child with type O blood. In fact, there is a 6.25% chance each of their children would have type O blood.

      If a child has Rh+ blood, one or both of the parents must have Rh+ blood. Two parents who are Rh- can not have a child with Rh+ blood.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  11. Tanya

    Hello Dr Greene,
    My mother is beside herself. She has 4 children, 2 are O+, one is A+, and one B+. She is A+ and my dad is O-. She is determined that the oldest isn’t hers because of some mix up in an army hospital. She was 17 and just arrived in the USA with my dad from Germany and at the time did not speak English. Is it possible to have a B+ child?
    Thank you for your response
    Sincerely, Tanya

    Added:
    • Cheryl Greene

      Hi Tanya,

      Thanks for writing in.

      If one parent has A+ blood and the other has O- blood they can have children who have A+, A-, O+ or O- blood. They can not have children with B+, B-, AB+, or AB- blood. However, it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to any conclusions. For instance, if one parent has type A blood and one has type B blood and one or both of the parents are Rh+ each of their children could be O+, A+, or B+.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  12. Karen

    Mother A+ father O+ child is AB-. Is this possible?

    Added:
    • Cheryl Greene

      Hi Karen,

      Our current understanding of genetics is that it is not possible for one parent to have type A+ blood, the other parent to have O+ blood and their child to have AB- blood. If one parent has A+ blood and if the other parent has O+ blood each of their children could have A+, A-, O+, or O- blood. However, it’s not uncommon for blood types to be different than they are thought. It is wise to have all three blood types retested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  13. Helen

    I have o+ and my husband has ab+. How does our child have o-?

    Added:
    • Cheryl Greene

      Hi Helen,

      Our current understanding of genetics is that it is not possible for one parent to have O+ blood and the other parent to have AB+ blood, and their child to be O-. It is possible for Rh+ parents to have children that are Rh-, but an AB parent can not have a child with type O blood. An AB parent can only have children who are A, B or AB.

      It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  14. Lauren

    Hey! Is it possible for a mother who is B+ and a father who is AB+ to have B- child? Everything I’ve looked up online says that it wouldn’t be possible. Thanks for your time!

    Added:
    • Cheryl Greene

      Hi Lauren,

      Thanks for writing in.

      I’m surprised that you are finding information that says it’s impossible for a mother to have B+ blood and a father with AB+ blood to have a child with B- blood. In fact, there is a 50% chance each of their children will have type B blood and a 6.25% chance each child will be Rh-. So you can rest assured, this is perfectly normal.

      If you’d like more information, please feel free to ask for more details.

      I hope that helps,
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  15. Br

    My brothers and sister are b+ and me o+ is it possible

    Added:
    • Cheryl Greene

      Hi Br,

      Yes! It is possible for siblings to have either type B+ or type O+. In this situation, at least one parent would have type B blood. The other parent could have type B, A or O blood. And at least one of the two parents would be positive for the D Antigen, or what we label Rh+.

      I hope that’s helpful.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  16. Ali

    Hi

    i am b+ and my wife A+ and we have new born with b-,is it possible?

    Thanks
    Ali

    Added:
    • Cheryl Greene

      Hi Ali,

      Thanks for asking your question.

      The short answer is, YES! This is completely normal. If you’d like the long answer, let me know and I’ll be happy to explain.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  17. Kavya

    Hi.. Can you please answer my question. The father blood type is O positive and the mother is O positive. Can the daughter have A positive? Thanks.

    Added:
    • Cheryl Greene

      Hi Kavya,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for two parents with type O blood to have a child with type A blood. Keep in mind, it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  18. Nyanjo

    Is it possible for parent of O+ have a child of B+

    Added:
    • Cheryl Greene

      Hello Nyanjo,

      Yes, it is possible for a parent to have O+ blood and have a child with B+ blood IF the other parent has B+, B-, AB+, or AB- blood.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  19. Jojo

    Hi,
    My blood type is O- and my brothers blood type is A+. I want to know if we have the same father. I don’t know what his blood type is and because we are estranged, he will not tell me. How can I figure out his blood type and if he is my father or my brothers father? The obvious answer is to get a paternity test but he is unwilling. Can you shed some light?

    Added:
    • Cheryl Greene

      Jojo,

      Great question. It is certainly possible for two people to be full brothers if their parents have the right combination of blood types. Do you know your mother’s blood type? If not, let’s assume she is type O+. That’s the most common blood type. If she does, your father would have to be type A+ or type A-. But that is not the only possibility. For instance, both parents could have type A+ blood and still have one child with type O- blood. Wild, right?

      There are also a few combinations of parents that would NOT work. For instance, if both parents had Rh- blood, they could not have a child with Rh+ blood. Or if both parents’ blood type was B, they could not have a child with type A blood. Or if either parent had type AB blood they could not have a child with type O blood.

      Blood types are only good for very broad grouping. You are right that a paternity test is the only way to know for sure.

      I hope you find a way to reconcile with your father, not only so you can resolve this question, but so you can both find comfort and peace.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  20. Elias

    Explanation not clear and as I understand there are contradictions.
    Since Rh- see that the blood of Rh+ is an enemy, how a parent with ++ or +- can have a child with Rh-?
    since A or B are dominant, how a child of type O, can has parent of type A or B if both are AA or BB?

    The worst if these two conditions are realized. A+,A+ how to get O- ?

    “This means that if both parents have Rh+ blood with the +- genes, they could have children who are ++, +-, or –. ”
    Or please explain the difference between Rh and the gene +, –

    Added:
    • Cheryl Greene

      Hi Elias,

      I’m so sorry this is unclear.

      The Rh system is completely different from the ABO system. Let’s discuss them separately.

      If someone is Rh+ it means they have the D Antigen in their blood. The D Antigen may or may not be passed to their children. If they don’t have the D Antigen in their blood they are Rh- and can not pass the D Antigen on to their children. The issues you cite above (“Since Rh- see that the blood of Rh+ is an enemy, how a parent with ++ or +- can have a child with Rh-?”) doesn’t apply since the blood is not ++ or +-. It’s either + or -. For more explanation on Rh- incompatibility, see Dr. Greene’s article How to Determine and Manage Rh Incompatibility.

      If both parents were Rh+ they could have children with Rh+ or Rh- blood. If one parent was Rh+ and the other was Rh- they could have children with Rh+ or Rh- blood. But if both parents are Rh- they can only have children with Rh- blood.

      Regarding type A, B, and O — A person with type A blood could be AA or AO and a person with type B blood could be BB or BO. Thus if one parent was type A and the other type B they could have children that had type A, B, AB or O blood.

      Please let me know if you have further questions.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  21. Kathy

    I am O positive and my child’s father is also O positive (he swears by this , got tested in high school through Red Cross ) my baby is A+ and had jaundice how is this possible ? Does this mean he wouldn’t be the father ?

    Added:
    • Cheryl Greene

      Hi Kathy,

      I hope you are doing well and not too stressed. Our current understanding of genetics is that it is not possible for both parents to have O+ blood, and their to have A+ blood. It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

      If there is a question about who the father is, a DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  22. Steve

    Dr. Greene,
    Is it possible for a parent (father) to produce 1 child with O- and 1 with A+? (different moms). No idea what dad or mom(s) types are.

    Added:
    • Cheryl Greene

      Hi Steve,

      Great question. Yes, it is possible for one parent to have one child with O- blood type and another child with A+ blood type.

      • For the child with type O- blood, both parents could have type A+, A-, B+, B-, O, or O- blood but could not have type AB+ or AB-.
      • For the type A+ child, one of the two parents must have type A blood and one of the two parents must be positive (+) or they can both be + for the D antigen. It could be either parent.

      Examples that work:

      • Parent 1 has Type B- blood, Parent 2 has type A+ blood
      • Parent 1 has Type A+ blood, Parent 2 has type A+ blood
      • Parent 1 has Type A- blood, Parent 2 has type O+

      If you’d like an explanation of how this works, let me know.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  23. Kathryn

    My father is A positive, my mother is B negative and my two sisters and I are all O positive. How is this possible?

    Added:
    • Cheryl Greene

      Hi Kathryn,

      Thanks for writing in.

      It is possible for one parent to have A+ blood and the other parent to have B- blood and for their children to have O+ blood.

      Blood types are comprised of two alleles for the “letter type”. Each person gets one letter allele from each parent. The most common letters (by far) are A, B, and O. It would be much clearer if our naming convention was more clear, but both type A and type B can have an O allele. Here is what that looks like:

      • Type A = AA or AO
      • Type B = BB or BO
      • Type O = OO
      • ype AB = AB

      Additionally, if either parent is Rh+, their child can be Rh+ or Rh-. It is only if both parents are Rh- that their children can only be Rh-.

      If your father has type A+ blood and if your mother has type B- blood, your sisters could have gotten an O allele from each parent and the D antigen (Rh+) from your father.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  24. Judith

    If Father is A negative and son is O negative what would the Mother be?

    Added:
    • Cheryl Greene

      Hi Judith,

      Thanks for writing in.

      If the father is A- and if the son is O-, the mother could be O+, O-, A+, A-, B+ or B-. She could not be AB+ or AB-. If you’d like to know why, let me know.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  25. Ashley

    When I was born my mom never tested my blood type and she doesn’t want anything to do with me cause once I found out what my blood type was she pushes me away cause I’m not the same blood type like her other 4 kids. I am the only child with one blood type when 4 of my biological siblings are 2 blood types my Brother and 3 sisters are AB+ Blood and I’m not I am only A+ Blood so does that mean they might not be my siblings and she may not be my birth mother. Everyone in her family says I look nothing like my birth mom so I was wondering if I should take a DNA test on Ancestry

    Added:
    • Cheryl Greene

      Hi Ashley,

      I can tell you are very concerned. Let me try to help.

      Blood types are comprised of two alleles — one from each parent. If your siblings have AB+ blood, they got an A allele from one parent and a B from the other, but that does NOT mean it would be impossible for you to have type A blood and still be full siblings.

      What we call type A blood is either an A allele from each parent (AA) or an A from one parent and an O from the other (AO). Both these combinations are called type A blood.

      Here are two scenarios that would work:

      1. One parent is A the other is B, but the B parent is BO. The child get an A allele from one and an O from the other and has type A blood.
      2. One parent is AB and the other is A. The child gets an A from both parents and has type A blood.

      Let me know if you’d like more clarification.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  26. Stephanie

    If both my parents and myself have rh + blood, does that mean that I am ++ and would definitely have an rh + child? Or is it still possible that I received a recessive rh – gene from my parents and therefore could still have an rh- child?

    Added:
    • Cheryl Greene

      Hi Stephanie,

      If a parent is Rh+ it means they are positive for the D Antigen. The parent may or may not pass that down to their children. If a parent is Rh-, it means they do not have the D Antigen and can not pass it down. Two Rh- parents can not have an Rh+ child, but two Rh+ parents can have children who are either Rh+ or Rh-.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  27. Nur

    Hi.. Can you please answer my question. The father blood type is AB and the mother is B. Can the daughter has O+ ? Thanks.

    Added:
    • Cheryl Greene

      Dear Nur,

      Thank you for writing in.

      If one parent has type AB blood and the other parent as type B blood, they can not have a child with type O blood. However, it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  28. Paul

    Hi, If mum is O+ and dad is O- then can the baby be A+?

    Added:
    • Cheryl Greene

      Hi Paul,

      Thanks for writing in.

      If one parent has type O+ blood and the other parent has type O- blood, they can have children with type O+ or O- blood, but they cannot have children with A+ blood. However, it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
    • Liabelle

      Hello. My mom Rh+O and dad rh-O and my sister rh+O but how is it possible that I’m rh+A ?

      Added:
      • Cheryl Greene

        Hi Liabelle,

        Likely one of the blood types is different than you think it is as our current understanding of genetics is that it is not possible for one parent to have O+ blood, the other parent to be O- and their child to have A+. Two parents with type O blood can only have children with type O blood.

        As a next step, it is wise to have all your blood retested.

        I hope that helps.
        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
  29. Alan

    Sir I have one case to handle,

    The Father is O+ and mother is O+
    but thier son is B+.

    Can this be possible ??

    Added:
    • Cheryl Greene

      Hi Alan,

      If both parents are O+ their children could be O+ pr O-, but they could not be B+.

      It’s not uncommon for blood types to be different than they are thought — perhaps one of the parent’s or the child. It is wise to have all your blood retested before drawing any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  30. Laritha

    Mum has A+ and Dad B+ can the daughter have AB+?

    Added:
    • Cheryl Greene

      Hi Laritha,

      Thanks for writing in and what a great question. The answer is YES! If mum is A+ and if Dad is B+, their child can have AB+ blood. If you’d like to know how that works, please let me know and I’ll be happy to explain.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  31. Kristine T

    A couple with a newborn baby is troubled that the child does not resemble either of them. Suspecting that a mix-up occurred at the hospital, they check the blood type of the infant. It is type O. Because the father is type A and the mother is type B, they conclude that a mix-up must have occurred. Are they correct? Prove your answer.

    Added:
    • Cheryl Greene

      Hi Kristine,

      Thanks for writing in.

      It IS POSSIBLE for one parent to have type A blood, the other to have type B blood and their child to have type O blood. Here’s why:

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O.
      — If a person has type A blood he or she has at least one A allele. He or she can have two A alleles (AA) but can also have one A and one O (AO). Both are called type A blood.
      — If a person has type B blood he or she has at least one B allele. He or she can have two B alleles (BB) but can also have one B and one O (BO). Both are called type B blood.
      — If a person has type O blood, both alleles are O (OO).

      In the example you gave the child could have gotten an O allele from each parent so would have type O blood.

      If there is still a question, a DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  32. Cheryl

    I have A positive blood, my mom is Rh negative and my dad’s is O positive, is this possible

    Added:
    • Cheryl Greene

      Hi Cheryl,

      Thanks for writing in.

      If you have A+ blood and if your dad has O+ blood, your mom could have A+, A-, AB+ or AB- blood. Does that answer your question?

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  33. Jana

    I’m AB- and both my parents are O+. I honestly didn’t think it was possible and people always tease me because I look nothing like them at all. my uncle was there when I was born so I know I’m not adopted either.

    Added:
    • Cheryl Greene

      Hi Jane,

      Thanks for writing in.

      If you have AB- blood you have to get an A allele from one parent and a B allele from the other. People with type O blood ONLY have O alleles. That is why it is considered impossible for two parents with type O blood to have a child with AB blood.

      It’s not uncommon for blood types to be different than they are thought. As a next step, it is wise to have all your blood retested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  34. Miriam

    Mother is A+. Father is A+. Can daughter be AB-

    Added:
    • Cheryl Greene

      Hi Miriam,

      Thanks for writing in.

      Each parent passes one allele down to their child and those two (one from mom and one from dad) make up the baby’s blood type.

      If a person has type A blood he or she has:

      1. one or two A alleles and
      2. can have one A allele and one O allele but
      3. can not have a B allele

      A person with AB blood has one A and one B allele.

      This means two parents with A+ blood can not have a child with AB blood.

      It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  35. EDWARD

    My father B+ and Mother is also O+ (Both deceased).. Can they give birth to O negative child as firtlst born

    Added:
    • Cheryl Greene

      Hi Edward,

      Yes, it is possible for one parent to have B+ blood, the other to have O+ blood, and any of their children to have O- blood.

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O.
      — If a person has type B blood he or she has at least one B allele. He or she can have two B alleles (BB) but can also have one B and one O (BO). Both are called type B blood.
      — If a person has type O blood he or she has two O alleles (OO).

      Rh+ means a person is positive for the D antigen. Rh- means a person does not have the D antigen.
      — If a person is Rh+, he or she can have a child that is Rh+ or Rh-.
      — If a person is Rh-, he or she can only have a child that is Rh+ if the other parent is Rh+.
      — Two parents with Rh- blood can not have a child with Rh+ blood.
      — Two parents with Rh+ blood can have children with Rh+ or Rh- blood.

      What all this means is if your father had B+ blood and if your mother had O+ blood they could have a child who is O- and that would be perfectly normal.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  36. Mahi

    Hi,

    Here I am Mahi

    My mom is AB positive and My dad is B positive and I am A1 positive. How could it be possible?

    Can you tell how it could be possible

    Added:
    • Cheryl Greene

      Hi Mahi,

      Thanks for writing in.

      If your mom is AB positive and if your dad is B positive, they could have a child that is A positive. A1 is a subtype of A. roughly 80% of people with type A blood are A1.

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O.
      — If a person has type AB blood he or she has one A allele and one B allele.
      — If a person has type B blood he or she has at least one B allele. He or she can have two B alleles (BB) but can also have one B and one O (BO). Both are called type B blood.
      — If a person has type A blood he or she has at least one A allele, but the other could be an O allele.
      — Rh+ means a person is positive for the D antigen.

      In the example you layout, if your mom has AB+ blood and if your dad has type B+ blood, you could have gotten an A from your mother and an O from your father. Your blood type would then be called type A. You could have gotten the D antigen (Rh+) from either parent.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Cheryl Greene

        Hi Vicki,

        Thanks so much for writing in.

        Dr. Greene has answered your question as a post so others can easily find it. You can see his answer here. Dr. Greene also, said “I also love your other thoughts on reducing spread – especially cleaning our phones!!”

        Thanks so much for your service. All of us staying at home appreciate the amazing work all of you are doing. You’re a hero!

        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
  37. Martina

    Hi, my husband and me are both RH0 -. And I do believe my both kids were 0 – as well. I remember they were 0 for sure, when they took bloods through the heel prick when babies, but cannot find the paper. I always thought they were 0 – like us, but my sister is telling me that they should be 0 + (not sure why)… could I be right and what I remember is correct?

    Added:
    • Cheryl Greene

      Hi Martina,

      Thanks for writing in.

      If two parents have type O blood and are RH-, they can only have children with type O, Rh- blood.

      None of our memories are completely accurate, so if blood types are important (such as needing a blood transfusion), they should always be rechecked.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  38. Barb

    Thanks for the explanation of Rh + and Rh- and how we inherit it. I am one of four siblings all of whom are Rh- while both of our parents were Rh+. I knew that they both had to have what I was taught to call a recessive Rh- gene but thought it was numerically impossible for all 4 of us to be negative.

    Added:
  39. Danna

    So my mother is 0+ my father is O- I am B+ how everyone is telling me my father isn’t my dad but he is saying I am his child I am 34 years old and going crazy I have a younger sister who is O- and a brother who is O+ I am the only child that is B+ please help me

    Added:
    • Cheryl Greene

      Hi Danna,

      Thanks for writing in.

      If two parents are O+, they can not have a child that is B+. So either one of your blood types is different than you think (this is often the case) or one of your parents is not your parent. Since your father is already talking about this with you, likely the easiest thing to do would be to tell him you are going crazy and you really want to know for sure. The only way to do that is for both of you to take a paternity test.

      DNA Paternity tests can be done at home and are very private. You can order them online and do the whole process by mail.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  40. Kelley

    I found out when my mom was very sick that she had A positive blood. I have A positive but my biological father, which I’ve never had anything to do with. I’m going to be meeting for the second time ever so, of course there’s some hesitation on both sides. Is he or isn’t he’s my father by blood with what I do know about my mom and my blood type? What kind of blood type which he have? Sincerely desperately need to know.

    Added:
    • Cheryl Greene

      Hi Kelly,

      Thanks for writing in and sharing your concerns.

      If your mother has A+ blood type, and if you have A+ blood type, your biological father could have A+, A-, B+, B-, O+, O-, AB+ or AB-. In other words, If your mother has A+ blood type and if you have A+ blood type, your biological father can NOT be determined by blood type. He could have any blood type. Why? How can this be? If you want to know the full reason behind this, write back and I’ll explain.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  41. Muriel

    IF.my dad.s blood group was AB.and my blood group is A rhesus positive why was my twin brother.s blood group O.
    Thanks

    Added:
    • Cheryl Greene

      Hi Muriel,

      Thanks for writing in and sharing your concerns.

      An AB parent can not have a child with type O blood. In your situation, I would try to have all your blood re-tested. Likely one of the blood types is not what you think it is. This is so common that blood types are tested before medical procedures that might require a blood transfusion even when a person is sure they know their blood type.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  42. Irish

    Hi.
    I just want to ask if there could be some cases of having an A+ child while both parents are type O??

    Added:
    • Cheryl Greene

      Hi Irish,

      Our current understanding of genetics is that it is not possible for two parents with type O blood to have a child with type A blood. Two type O parents can only have children with type O blood. But …

      It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  43. Charity

    Hi.

    One of my parents is A- and the other is O-. Imagine my surprise to recently learn that I am O+. When I spoke to my parents about the results of my recent test, they agreed it was the same blood type the hospital shared with them when I was born.

    Is it possible for both of my parents to be my true biological parents?

    Thanks for your time.

    Added:
    • Cheryl Greene

      Hi Charity,

      Thanks for writing in. If one parent has type A blood and if the other has type O blood, they could have a child with type O blood. But if both parents are Rh- they can not have a child with Rh+ blood.

      It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before making any assumptions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  44. Joy

    Hi,

    Could you help me? just to make my mind clear.
    i have a daughter which is AB+ and my blood type is B+…
    i had an affair with other guys during that time.

    Now, i had read on the internet that B+ and O+ is an impossible match for a AB+ child, the other guy is O+. i didn;t know the blood type of the other guy yet.

    does b+ and o+ is impossible to have an ab+ offspring?

    Thanks

    ChinChan

    Added:
    • Cheryl Greene

      Hi Joy,

      Thanks for writing in.

      If your blood type is B+ and if your daughter’s blood type is AB+, her father would have to have type A+, A-, AB+ or AB-.

      Blood types alone can not be used to determine paternity, but some times blood type can be used to rule out a possible parent. You are correct that a child with AB+ blood can not have a parent with O+ blood.

      If you are concerned about who the father is, the best test is a DNA paternity test.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  45. KE

    I am A positive and my ex-husband has rh positive blood.
    I had an affair with a man who is O positive.
    My daughter is A negative.
    Which one is likely to be the father.

    Added:
    • Cheryl Greene

      Dear KE,

      Thanks for writing in.

      Sometimes you can eliminate a potential father, based on blood type, but it is impossible to determine paternity from blood type. If you have A-positive blood, and if your ex-husband has Rh-positive blood, and if the man you had an affair with has O-positive blood and if your daughter has A-negative blood, either man could be the father. The information you have does NOT eliminate either man.

      A DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  46. Janie

    My husband and I both have A Negative blood types. Does that mean our children also have A Negative blood? My child of 29 years has multiple health problems. Could this be the reason?

    Added:
  47. Lorenzo

    Me and my wife are A+. Our first born is A+ but our 2nd child is O+. Is that possible? Thank you

    Added:
    • Cheryl Greene

      Hi Lorenzo,

      Yes! This is possible. In fact if two parents have type A+ blood, there is a 93.75% chance each of their children will be Rh+, a 93.75% chance each child will have type A blood, and a 6.25% chance each child will have type O blood.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  48. Hana

    my dad is AB negative and my mom is O positive and my blood group is A positive are they my parents

    Added:
    • Cheryl Greene

      Hi Hana,

      Blood types can not determine if two people are your parents or not, but in some instances, they can determine that two people aren’t your parents. In other words, there are a lot of people with the same combination of blood types, so blood types can only say “this combination is a possibility or is not a possibility”.

      In the situation you describe, if your dad has AB- blood and if your mom has O+ blood, and if you have A+ blood, they could be your parents.

      Each parent gets one allele from each parent. In this example, the child got an A from the father and an O from the mother and would have AO blood type. We call that type A blood. If either parent is Rh+ and passes that down to their child, the child’s blood is Rh+.

      If you still have questions about paternity, DNA testing will provide the answers. Blood typing will not.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  49. Ni’Julum Brown

    I’m curious on do the dad and child suppose to have the same blood type . I’m O+ he’s O- and my child is O-

    Added:
    • Cheryl Greene

      Hi Ni’Julum,

      Each child gets half the code for their blood type from each parent. In some cases that means the child has a different blood type than either parent because it’s a combination of the two.

      If one parent has O+ blood and the other has O- blood, their children can be either O+ or O-. Both are completely normal.

      Please let me know if you’d like a more indepth answer.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  50. Danielle

    I’m curious after reading this thread. I am O+ but both of my parents aren’t. I have 3 siblings and I’m the only one that’s O+
    I have health issues and I’m starting to feel freaked out. Hopefully I can get some answers. Thank you.

    Added:
    • Cheryl Greene

      Hi Danielle,

      I doubt there’s a reason to freak out. If you are O+, your parents could be O+, O-, A+, A-, B+ or B-. The only blood type that neither one of them could have is AB+ or AB-.

      If you’d like to know more about why that is, let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Danielle

        What a relief. Thank you very much.

        Added:
  51. Dana

    My dad was o positive my mom is o negative with rh negative. I am A negative with rh negative. Is this possible?

    Added:
    • Cheryl Greene

      Hi Dana,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for two parents with type O blood to have a child with type A blood. However, it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

      If you want further explanation, please let me know.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  52. Sandya

    Hi
    I am B negative – RH negative. My mother is B Positive and my father was AB Positive. How am I RH Negative if both my parents were Positive?

    Added:
    • Cheryl Greene

      Hi Sandya,

      This can be very confusing, but just because both parents are Rh-positive, they don’t necessarily pass it down to their children, in fact, there is a 6.25% chance that each of their children will be Rh-negative.

      If you have further questions, don’t hesitate to ask.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  53. Joshua

    Hi I’m blood type B+ and so are my two younger siblings however my father is blood type A+ and my mother is blood type O+ is this possible?

    Added:
    • Cheryl Greene

      Hi Joshua,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to have type A+ blood, the other parent to have type O+ blood and their child to have type B+ blood. Parents with these two blood types could have children with blood types: O+, O-, A+ or A-.

      It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  54. Jadon

    Hi, Is it possible for me to have O+ blood if my Mom is B+ and my Dad is O+?

    Added:
    • Cheryl Greene

      Hi Jadon,

      YES! This is a very normal outcome.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  55. KAREN A RIGG

    Hi my blood type is 0 neg and my sister is A pos , my father is 0 neg, not 100% sure about my mother (deceased) but I think she was o neg as well , is it possible that my sister could be my fathers daughter or due to her blood type would her father be different

    Added:
    • Cheryl Greene

      Hi Karen,

      Every child gets one allele for blood type from each parent. It doesn’t matter which parent provides which allele.

      If your father has type O- blood, he’s not ruled out as the father of a child with A+ blood — if the child’s mother had type A+ or AB+ blood.

      If the mother had type O-, then she could not have a child with A+ blood — unless the father had type A+ or AB+ blood.

      Since you don’t know your mother’s blood type for sure, you can’t make any conclusive determination about your or your sister’s parentage.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
    • Sheila Brown

      Hi, I’m so confused in how to know my mother’s blood type and my biological father’s blood type, my half brother’s blood type is RH positive and mine is O positive, and I don’t know what my half brother’s father’s blood was either

      Added:
      • Cheryl Greene

        Hi Shelia,

        I can see why you are confused. You simply don’t have enough information to begin to make guesses —

        O+ is the most common blood type. Children with O+ blood could have parents who are O+, O-, A+, A-, B+ or B-. But you have ruled out either parent having AB+ or AB- blood.

        RH is not a type. It’s part of the name used for + or – blood. So if you are O+, you would technically be O Rh+.

        Even if you had your correct full blood type, your half brother’s full blood type, and his father’s blood type, you may not be able to rule out very many types from your parents. As you can see, if any of you have type O blood, you haven’t narrowed down the possibilities much.

        Sorry!

        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
  56. Janie

    My mom is A-, my dad is O+. I’m also A- like my mom, but my sister is AB+. When I was studying blood types, it stood out to me that my sister’s blood type compatibility didn’t match the chart I was looking at.

    It’s to my understanding that AB+ blood with A- and O+ parents isn’t even supposed to be possible. I confronted my mother years ago about it and got no clear answers. She was angry with me for questioning it and told me to drop it.

    Another odd thing: My mom has blue eyes, my dad has green eyes. I have blue eyes like my mother. My sister has dark brown eyes. So, there’s the seemingly impossible bloodtype combo and nearly impossible eye color combo.

    I seriously don’t think we have the same father. I think we’ve been lied to. I stopped questioning our mother because she refused to discuss it. I will always think it’s suspicious though. What are your thoughts? Could it be possible for her to be AB+ and have A- and O+ parents…even a small chance?

    Added:
    • Cheryl Greene

      Hi Janie,

      Our current understanding of genetics is that it is not possible for one parent to be A-, the other parent to be O+ and their child to be AB+. If your parents do have A- blood and O+ blood, they could have children have O+, O- A+ or A- blood.

      It’s not uncommon for blood types to be different than they are thought, but your mother’s attitude likely makes this impossible.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  57. Carolyn Dukes

    I’m a RH negative mom and my husband is AB negative. Our child is O positive. We went to the blood bank and asked them what blood type are child would be. They said that the blood type could be O AB A B negative but it could also be O AB A B positive. Now this was 40 years ago. They said this is because they are rare blood Types.

    Added:
    • Cheryl Greene

      Hi Carolyn,

      Forty years is a long time. Perhaps the blood bank then didn’t know as much as we know now, or perhaps your memory of what they said is a bit foggy.

      Here is our current understanding:

      • A parent with AB- blood can only have children that have type A or B or AB blood, depending on the blood type of the other parent.
      • Two Rh- parents can’t have a child with Rh+ blood
      • Type AB blood is the rarest type
      • The only combination of parents that could result in any possible outcome (O+, O-, A+, A-, B+, B-, AB+, AB-) is one parent with type A blood and the other with type B blood and at least one parent that is Rh+, but the other could be Rh+ or -.

      If you are still curious, you’ll need to have new blood type tests for the three of you.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
    • John

      My father is o positive and my mother is AB negative and me and my sister both are 0 positive to my understanding I should be neither A or B and there is no chance I can be o positive

      Added:
      • Cheryl Greene

        Hi John,

        If your father has O+ blood and if your mother has AB- blood, all their children would have A+, A-, B+ or B- blood.

        It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

        I hope that helps.
        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
      • Carolyn Dukes

        John, you said your father was O positive and your mother was AB negative. Then you said you and your sister were O positive. That would mean you could be O positive unless you meant your father was O negative?
        In my case I’m RH negative and my husband was AB negative and we had a O positive baby. We went to the blood bank at the county hospital and asked them what blood type our child could be and they said the baby could be AB negative, RH negative, A or B negative or positive. Also it could be RH negative or positive, or AB negative. We had a positive O baby. My sister and her husband bought had negative blood types and they had a positive baby too. Anyway the hospital told us our baby could be any blood type because two negatives can make a positive. But my child swears her dad couldn’t be her father. I don’t get it because when I had my first child they announced on the radio for people to donate blood if they were RH negative blood type because at the time my blood type was very rare.

        Thanks, Carolyn

        Added:
  58. Victoria

    Very nice one
    I love that

    Added:
  59. djd dutta

    plz give me the answer,if parents both are Rh positive,then their child will be?

    Added:
    • Cheryl Greene

      Hello,

      If both parents are Rh+ their children can be Rh+ or Rh-. If one parent is Rh+ and the other is Rh-, their children can be Rh+ or Rh-. But if both parents are Rh-, their children can only be Rh-.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  60. Nika

    Hi can you help me sir. My mother and my father is same type o. And my brother and sister is type o. But only me is type b+.

    Added:
    • Cheryl Greene

      Nika,

      Our current understanding of genetics is that it is not possible for two parents with type O blood to have a child with type B blood.

      It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  61. Amy

    My sister-in-law is has AB blood, her mother is O+ and her father is O-. Both her siblings have O blood. How does she have AB?

    Added:
    • Cheryl Greene

      Hi Amy,

      From all the science and testing we have now, it is believed that two parents with type O blood, can not have a child with type AB blood. There is no reason to think that science is in question.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
    • Katie

      If I am B- my sister is AB- and my other sister is O- our mother is A- what is my father’s blood type?

      Added:
      • Cheryl Greene

        Hi Katie,

        If three full siblings have types B-, AB- and O-, then one parent must have type A- or A+ blood and the other must have type B- or B+ blood. That is the only combination of parents that could result in their three children having B-, AB- and O- blood.

        I hope that helps.
        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
  62. Jackie

    My mother is A- I’m O positive, my brother is O- what is our fathers blood type ?

    Added:
    • Cheryl Greene

      Hi Jackie,

      If your mother’s blood type is A- and if you are O+ and your brother is O-, and if you have the same father, he could have A+, B+ or O+ blood.

      Please let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Jackie

        Thanks for your reply. I’m not sure of my father’s blood type. I have used a parent blood type calculator. If my mother is A- and I’m O positive then my father would be positive. But, if my mother is – and my brother is – then the father would be -. For this reason I’m not sure of my father.

        Added:
        • Cheryl Greene

          Hi Jackie,

          You are mostly correct. The one false assumption is that if your mother is Rh- and your brother is Rh- the father must be Rh-.

          Rh+ simply means the D Antigen is present in the blood or the blood is positive for the D Antigen. If it is present it may or may not be passed along. If it’s not present, it can not be passed on to a child, thus two Rh- parents will always have an Rh- child. But the opposite is NOT true – if one parent is Rh- and one child is Rh- the other parent must be Rh-.

          In the case of one parent with Rh+ blood and one parent with Rh- blood, there is actually a 25% chance that the Rh+ parent would not pass on the D Antigen and each of their children could be Rh-. (If the two people had 100 children, 25 of them would be Rh-. Like flipping coins, you’ll know it doesn’t go 3 heads, then 1 tail. The order is random, but it equals 25 out of 100 over time.) In fact, even if both parents are Rh+ there is a 6.25% chance that the D Antigen won’t be passed along and each of their children could be Rh-.

          Regarding the parent blood type calculator, I don’t know why you would get a different result, but that is simply not the correct outcome. Most calculators offer results as Parent One, Parent Two, % of Children AND Parent One, Child, Possible Parent Two. Put both scenarios into a calculator and see what you get. Likely, the first (Parent One, Parent Two, % of Children) will get the outcome that I outline above. That is the correct one.

          I hope that helps.
          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          I hope that helps.
          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          Added:
          • Jackie

            Thanks so much for the reply. It helps a lot. The second part of the parent calculator for just one parent. I use A- my mother because I’m sure. One child I’m O positive. It says father would be A/B/O positive. If I use my mother again and my brother O – it says, father is -. So I have a positive father and brother has a negative father.

            Added:
          • Cheryl Greene

            Hi Jackie,

            I tried it on a calculator, too. I got the same results that you got, but I don’t trust them. They just don’t make sense to me. Anyone else want to chime in?

            Best, @MsGreene
            Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

            Added:
  63. Christy

    Hello,

    I am O+, my Mother is B- and my Father is A+. My Mother says it is impossible for me to have O+ blood and I should get re tested is this correct ?
    Thank you

    Added:
    • Cheryl Greene

      Hi Christy,

      Thanks for writing in with your question.

      If your mother has B- blood and your father has A+ blood there is a 6.25% each of their children will have type O blood and a 75% chance each child will be Rh+.

      If you’d like an explanation of why that is, let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  64. HR

    Hello…

    I keep reading everything that you have written on this page and in the comments, and I guess I just need to hear it again? I am B+ and both of my parents are O+. Both of my parents have had cancer and extensive blood work, and I have had my blood work done numerous times. Does this really mean my father isn’t my genetic father? I am scared to get a genetic test… but I can’t stop thinking about it… He never liked me as much as my brother, but my mom told me he was and if he wasn’t, she took it with her when she passed.

    Added:
    • Cheryl Greene

      Hi HR,

      You are right, as far as we know, two parents with type O blood can’t have a child with type B blood. There are extremely rare cases, that I doubt fit your circumstances, where a person with reported type O blood actually has type hh (Bombay). Our test results can’t differentiate between OO and hh, so they are read as O. BUT this wouldn’t result in type B blood in the child. Might there be some other wild anomaly? Something that is ahead of our blood typing technology? If so, that should show up on DNA testing.

      Here’s the thing — if your mother is no longer living, you can’t ask her. That means to get any more clarification you would need to talk to your father and perhaps even do a DNA test. What will it do to your relationship with your father if he finds out for the first time that you are not his child? Or maybe he knows and just talking about it will help you both? I don’t know if there’s a way to predict the outcome. It may come down to figuring out what you can live with and what you can not.

      Sorry I couldn’t be more helpful.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  65. kailash

    if the mother blood is o positive.and father blood is o negative then what will be the blood of children

    Added:
    • Cheryl Greene

      Hi Kailash,

      Thanks for writing in.

      If one parent is O+ and the other is O-, all their children will have type O blood.

      If they had 100 children (which no two people will have) 75 would have O+ blood type and 25 would have O- blood. If they have two children, it would be perfectly normal for them to be either O+ or O-. The averages only apply over large groups.

      I hope that’s helpful.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  66. Gavin Monroe

    Hi, I’ve donated blood in the past and it came to me as a surprise that I’m O+, but both of my parents are O-. It that even possible?

    Added:
    • Cheryl Greene

      Hi Gavin,

      Thanks for your question.

      Our current understanding of genetics is that it is not possible for two Rh- parents to have a child with Rh+ blood. The Rh+ means the blood is positive for the D Antigen. If neither parent is positive, they can’t pass it along to their children.

      However, it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  67. Elixabeth

    If a mother is A+ and a Father is A+, how likely is it they will have two children who are O+? My parents have always told us they are A+. My sister recently got typed as part of a pre nursing health class. Her type came out as O+. I was curious so I ordered an at home blood test (Eldon Home Kit HKA 2511-1) and the test shows I am O+.

    Added:
    • Cheryl Greene

      Hi Elixabeth,

      If both parents have A+ blood, the likelihood that each of their children will have type O blood is 6.25%. (That means if they had 400 children, 25 of them would have type O blood.)

      The likelihood that each child will be RH+ is 93.75%.

      Like tossing coins to see how many heads and how many tails, the number averages out after a lot of throws, but the first few may all be the same.

      In other words, there’s not reason so suspect two A+ parents aren’t the parents of two O+ kids.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  68. Bella

    Is is normal to get the blood type of both parents? I’m ab positive. My parents are a positive and b positive? Is combining both blood types common?

    Added:
    • Cheryl Greene

      Hi Bella,
      Thanks for your questions.
      It’s not only normal, it is the way it works. Every person gets one blood type gene (in the form of alleles) from each parent. This can be confusing because blood type names don’t always indicate what alleles each type has. As an example, blood type B can have B and O alleles, but they always have at least one B allele. Type A can have A and O alleles, but they always have at least one A allele.
      If your parents and type A and type B, they could have children with type AB, A, B or O blood.
      I hope this is helpful,
      @MsGreene

      Added:
      • Bella Johnson

        My mom said it’s rare to have both since she’s a nurse. Thanks

        Added:
  69. Nahian

    Is it possible for a child to have AB negative blood when the father is AB positive and the mother is A positive?

    Added:
    • Cheryl Greene

      Hi Nahian,

      Yes, it is possible. In fact, there is a 37.5% chance their child will have AB blood type and a 6.25% chance their child will be Rh negative.

      If you’d like further explanation, please let me know.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Nahian

        Thank you.

        Added:
  70. Rohan

    Sir, Me and my wife are O positive but our child is A Positive. Is it Possible ??

    Added:
    • Cheryl Greene

      Rohan,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for both parents to have O+ blood and their child to be A+. An O parent can only have children who have type O blood.

      It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

      There is, however, a very rare blood type (0.0004% or about 4 per million in the general population) known as the Bombay Blood type. In some places such as Mumbai (which was formerly called Bombay) the occurrences can be as high as 0.01% or 1 in 10,000. This group does not fall into the ABO system and the usual tests for ABO blood show them as group O.

      That means if either you or your wife had the Bombay type, those results would read as type O even if they weren’t and that would throw everything off. This would be extremely rare.

      DNA paternity tests are considered accurate (99.999%) and are considered the only accurate test for paternity. If you want to pursue this further, a DNA test is the next step.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  71. Wendy

    Is it possible if I am A positive that my parents are A positive and O positive?

    Added:
    • Cheryl Greene

      Hi Wendy,

      Yes, it is completely normal for an A+ parent and an O+ parent to have an A+ child.

      If you have questions about how this works, let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  72. Melanie

    I just found out that I’m B+, my father is O+ and mother is RH O. How am I B+?

    Added:
    • Cheryl Greene

      Dear Melanie,

      Our current understanding of genetics is that it is not possible for both parents to have type O blood and their child to have type B blood. Two parents with type O blood, can only have children with type O blood.

      It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  73. Rosanna

    Well Think I must say this then…it is possible for newer scientific research into blood groups. My daughter is B+ I am O+ and her father is O- and she is DEFINITELY ours. So it IS possible for O parents to have a B child or NON “O” child.

    Added:
    • S Smith

      Please could you tell me if an o positive mother could have a b negative child, blood group of the father unknown, thank you.

      Added:
      • Cheryl Greene

        Dear S,

        Yes, it is possible for an O+ mother to have a child with B- blood. The father’s blood type would be B+, B-, AB+ or AB-.

        I hope that’s helpful.

        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
  74. Sandy

    I am Rh neg Why did this not affect my first child?

    Added:
    • Cheryl Greene

      Hi Sandy,

      Dr. Greene wrote a whole article about this. Here are a few excerpts:

      “People are called Rh-negative if they do not have the rhesus (Rh) protein on the surfaces of their blood cells. If Rh-positive blood cells get into the bloodstream of someone who is Rh-negative, the body of that Rh-negative person will see this as an enemy invasion.

      Unprepared, the Rh-negative person will begin to make antibodies (what you call anticorps) against the foreign Rh protein. This first exposure is often not even noticed. The next time an exposure occurs, though, the body is primed to seek and destroy all Rh-positive blood cells. All-out war can occur inside an Rh-negative person’s body…The first pregnancy is rarely a problem because blood is often not exchanged until the time of birth.”

      You can read more about How To Determine and Manage Rh Incompatibility in his article.

      I hope that’s helpful.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  75. Ashley

    Is it possible for A+ and O- to make O+

    Added:
    • Cheryl Greene

      Hi Ashley,

      Yes, it is possible for one parent to have A+ blood, the other to have O- blood and their child to have O+ blood. In fact, there is a 25% chance the child will have type O blood and a 75% chance he or she will be Rh+.

      If you’d like further explanation, please let me know.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  76. Kate

    My husband is O negative, and I am B negative. My first child is B+. We’ve had his blood drawn three different times, and it always comes back B+. How is this possible?

    Added:
    • Cheryl Greene

      Hi Kate,

      If a person has Rh- blood that means the D antigen is not present. Rh+ blood means the D antigen is present. Theoretically, if neither parent has the D antigen in their blood, they can not pass it along to their child.

      You might consider having both parent’s blood retested. If all the results come back the same, you might consider a DNA test for all three parties.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  77. Jennifer M

    If Mother is B- and father is O+, can i (child) be A+?

    Added:
    • Cheryl Greene

      Dear Jennifer,

      Our current understanding of blood types is if one parent is B- and the other parent is O+, they can not have a child with A+ blood. Their child could have Rh+ blood, but not type A.

      If you’d like an explanation, please let me know.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  78. Rhonda

    I cannot find any information about 0+ parents having an RH- baby, both my Husband and I are 0+ and my daughter is RH-, could you please explain how this was possible, she is 35 now and when she was born the nurse tried telling me that it was impossible for her to be her father’s and I told her that she was wrong, that he was her father and that she needed to do some research to show that to be true. Well she came back to me two days later and confirmed that while it is possible, it is as rare as an RH- blood type.

    Added:
    • Cheryl Greene

      Hi Rhonda,

      It is perfectly normal for two O+ parents to have an O- child. Rh+ means the presence of the D antigen. Rh- means the absence of the D antigen. 6.25% of children with two Rh+ children are Rh-. On the other hand, two parents that are Rh- do not carry the D Antigen and can not have a child that is Rh+. Sounds like your nurse had the two mixed up.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  79. Johnny

    Hi,
    I am O+ and my wife is A. Our daughter is AB negative. Is this possible?

    Added:
    • Cheryl Greene

      Hi Johnny,

      If one parent is O+ and the other is A, they can have children that are A+, A-, O+ or O-. They can not have a child that is AB- or AB+.

      Before jumping to any conclusions, it’s wise to have all your blood retested. It’s not uncommon for blood types to be different than people think they are. If there’s still a question after retesting, DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Robin

        It is possilbe to have an O parent produce an AB child. Rare but still possible and has happened. I am one of those children. Research a little deeper.

        Added:
  80. SW

    Hello! Is it possible that both of my parents are A and I am AB?????

    Added:
    • Cheryl Greene

      Hi SW,

      First, it is not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to any conclusions.

      With that in mind, it is not possible for two parents with type A blood to have a child with type AB blood. Two type A parents can have children that are type A or O.

      If there is a question, a DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  81. Sneha

    I am having B- blood group and my brother also having the same but my mother is O+ and my father is A+ so how is it possible that me and my brother are B- please help me to determine that they are my actual parents or not. Your help will be appreciable.

    Added:
    • Cheryl Greene

      Hello Sneha,

      It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before making an assumption of this size, but our current understanding of genetics is that it is not possible for one parent to be O+, the other parent to be A- and their child to be B-.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  82. whitney sharp

    SO i want to ask this since im seeing this now. my mom is o+ and my dad is a or b something how is it that im O+ as my mom?

    Added:
    • Cheryl Greene

      Hi Whitney,

      First, it is normal for the child of parents who have type A or B blood to have type O bloood. Here’s why…

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O.
      — If a person has type A blood he or she has at least one A allele. He or she can have two A alleles (AA) but can also have one A and one O (AO). Both are called type A blood.
      — If a person has type B+ blood he or she has at least one B allele. He or she can have two B alleles (BB) but can also have one B and one O (BO). Both are called type B blood.

      Rh+ means a person is positive for the D antigen. Rh- means a person does not have the D antigen.
      — If a person is Rh+, he or she can have a child that is Rh+ or Rh-.
      — If a person is Rh-, he or she can only have a child that is Rh+ if the other parent is Rh+.
      — Two parents with Rh- blood can not have a child with Rh+ blood.
      — Two parents with Rh+ blood can have children with Rh+ or Rh- blood.

      What all this means is if your mom is O+ and if your dad is A or B they could each pass down an O allele and your mom could pass down the D antigen and they could have a child who is O+. That would be perfectly normal.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  83. LeeAnn Jones

    Is it possible for father to be o- and mother to be AB and have a B Rh + child?

    Added:
    • Cheryl Greene

      Hi LeeAnn,

      Yes, it is possible for one parent to have type AB blood, the other parent to have type O blood and their child to have type B blood. At least one parent must be RH+ for their child to be RH+. In this case, if the mother was RB+ and if the father was O- the child could be B+.

      If you’d like an explanation of how that works, let me know.
      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  84. Sedona

    If the mother is O Negative and the baby is O Negative could the Father be either a positive or B positive

    Added:
    • Cheryl Greene

      Hi Sedona,

      Thanks for writing in.

      If a mother is O- and the father is A+, their baby could be O-. If the mother is O- and the father is B+, their baby could also be O-. In fact, if a mother is O- the father could be Rh+ or Rh- and only blood group the father could not be is AB.

      I hope that’s helpful.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  85. Lrey

    If mother is A- and has a baby that is O+, who would be the father? Father with O+ blood type of father with B+ blood type?

    Added:
    • Cheryl Greene

      Hi Lrey,

      In this situation, if the mother has A- blood and if the baby has O+ blood, neither man with O+ or B+ blood can be ruled out. In other words, the father could be either man.

      If there is a question, a DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  86. Susan

    Hi, I don’t know my parents’ blood types, and both have passed.

    My sister is RH negative, as is her daughter.

    I’m O positive. Is this possible?

    Added:
    • Cheryl Greene

      Hi Susan,
      It is possible for the same two parents to have children who are Rh+ and Rh-, with one exception. If both parents are Rh-, they can only have Rh- children. Likely your parents were either Rh+ and Rh+ or Rh+ and Rh-.
      I hope that helps. Best, @MsGreene Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  87. Lovely

    Hi. I always thought I had an O blood type but getting hospitalized after an accident revealed I was actually B+. If my mom is O+ and my dad is O+ and all my siblings are O+, how did I become B+?

    Added:
    • Cheryl Greene

      Hi Lovely,

      Our current understanding of genetics is that it is not possible for two parents with type O blood to have a child with type B blood. If both your parents are O+, they could have children with O+ or O- blood, but it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Any

        Hi ,I’m any,my parents are both type O,why I become type B-,its is possible I’m not their child?

        Added:
        • Cheryl Greene

          Hi Any,

          Our current understanding of genetics is that it is not possible for two parents to have type O blood and their child to have type B blood. If both parents are type O, the can only have children with type O blood.

          However, it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to any conclusions.

          I hope that helps.
          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          Added:
  88. Bethany

    Hi Dr. Greene,

    Is it possible for a mother and father that both have type B blood to have a child is with type A blood and another child with type O blood?

    Added:
    • Cheryl Greene

      Hi Bethany,

      Our current understanding of genetics is that it is not possible two parents with type B blood to have a child with type A blood, but they can have a child with type O blood.

      It’s not uncommon for blood types to be different than they are thought. It is wise to have both parents and the child with type B blood retested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  89. Gautam

    Hello Dr.
    I just want to ask, can a mother with AB + blood group give birth to O + in any case??

    Added:
    • Cheryl Greene

      Gautam,

      Our current understanding of genetics is that it is not possible for one parent to be AB+ parent to have a child that is O+.

      Can a mother with AB+ blood give birth to a child with O+ blood in any case? There is a very rare blood type, called Bombay, that falls outside the ABO system. If a person has that type, he or she shows up as type O, but both parents must be carriers. I don’t think that would fit with an AB blood type.

      In this case, it would be wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought. DNA paternity tests are still accurate (99.999%) with type hh blood and are considered the only accurate test for paternity.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • leif evans

        I asked this same question, I found out that I am indeed a Bombay child, My mum was AB+ and I am O+, don’t know my fathers type, he died when I was 4

        Added:
  90. Rox

    Mother O-. Two kids AB-, other three kids A-. How is it possible that she is the mother of the AB- kids?? Her blood has been tested multiple times. She had to have a transfusion when she gave birth to my oldest sister and they had to have type O- transported in because they did not have any in the local blood banks. (1959)
    I wonder if she is really type A but keeps retesting as type O for some reason. Is that possible?? Maybe the transfusion worked out because O- is the universal donor. Scratching my head.

    Added:
    • Cheryl Greene

      Rox,

      That is very curious. There is a very rare blood type (0.0004% or about 4 per million in the general population) known as the Bombay Blood type. In some places such as Mumbai (which was formerly called Bombay), the occurrences can be as high as 0.01% or 1 in 10,000. This group does not fall into the ABO system and the usual tests for ABO blood show them as group O.

      The Bombay blood type is usually only found in small communities where there are other people with the Bombay or hh blood type. Both parents have to be h carriers, though a parent can be a carrier without actually having Bombay type blood.

      If you suspect your mother may have the Bombay blood type she can talk to her doctor about a specialized test for this blood type as it does not show up using the normal ABO blood type tests.

      DNA paternity (in this case maternity) tests are still accurate (99.999%) with type hh blood and are considered the only accurate test for paternity / maternity.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  91. Robert work

    Mother is o positive dad is a negative, can child be o positive

    Added:
    • Dr. Alan Greene

      Hi Robert,

      Yes! If one parent is O+ and the other is A-, their children can be O+.

      Here is a list of the blood types their children can have:
      — O+
      — O-
      — A+
      — A-

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
    • Fara

      Dr: Green,

      Both of my parents (supposed) are O+, my blood type and s A-, what is the probability of this. It should be noted my brother is O+.

      Added:
      • Cheryl Greene

        Hi Fara,

        Our current understanding of genetics is that it is not possible for two parents with O+ blood to have a child with A- negative blood. Two parents with O+ blood can only have children with O+ or O- blood.

        It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

        I hope that helps.
        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
  92. Kim

    If my mom is A+ and my father O-then is it possible for them to have a child with AB?

    Added:
    • Cheryl Greene

      Hi Kim,

      Thanks for your question.

      Our current understanding of genetics is that it is not possible for one parent to have type A+ blood, the other parent to be O- and their child to have type AB blood. An AB child can only have parents that are A and B, or A and AB, or B and AB.

      It is wise to have all three blood types retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  93. kat

    Hello, can i ask if my father was AB neg and my mother was 0 positive why I have 0 neg blood, both my sisters are A neg and B neg, this makes my dad not my biological father right???.

    Added:
    • Cheryl Greene

      Hi Kat,

      Thanks for writing in.

      You are correct that a parent with type AB blood can’t have a child with type O blood. But it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before drawing any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  94. Alok

    Hi
    Can A- father and AB+ mother have o+ child

    Added:
    • Cheryl Greene

      Dear Alok,

      This is a very interesting question. If a parent has A- blood, he or she can have a child with O+ blood, if the other parent is Rh+. But a parent with AB+ blood can not have a child with O+ blood. A person with AB blood can only have children with A, B or AB blood (depending on the blood type of the other parent).

      It’s likely wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  95. Ann

    Hi There ,

    Wife is o+ , husband is o+ , i delivered twins and records shows their blood type is b+.
    Is that possible ? first born and 2nd born are both o+. We are both certain that these twins are “ours”

    Added:
    • Cheryl Greene

      Hi Ann,

      If two parents have O+ blood, their children can only be O+ or O-. It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  96. Puru

    Hello

    My brother has AB+ blood group though both my parents have B+ blood groups. I called a DNA testing centre and they said that the child can have AB+ but not AB-. Is it possible? How does it happen? Can you refer a study explaining this phenomena?

    Added:
    • Cheryl Greene

      Hello Puru,

      I can see your need for clarification.

      Our current understanding of genetics is a person with AB blood type has to get the A from one parent and the B from the other. That means the two parents can be:
      — AB and AB or
      — AB and B or
      — AB and A or
      — A and B
      — But both parents cannot be type B

      The Rh system is completely different from the ABO system. Rh+ simply means the D Antigen is present in the blood. Rh- means it is not. Two Rh+ parents do not necessarily pass down the D Antigen, so two Rh+ parents can have a child that is Rh+ or Rh-. Since the D Antigen isn’t present in people who are Rh-, two Rh- parents can’t have a child that is Rh+.

      Perhaps what the person at the DNA company meant was two B+ parents could have a child that is Rh-, but they couldn’t have a child that has type AB blood.

      If that doesn’t answer your question, I’m afraid you’ll have to get back in touch with the DNA company that gave you that information.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  97. Rhiannon

    Hi,I have 2 potential dads and hope you can help,my mother is o+ and one potential is o+ too,I am b-.This man cannot be my biological father can he?

    Added:
    • Cheryl Greene

      Hi Rhiannon,

      You are correct. If your mom has O+ blood and if you have B- blood, your father cannot be O+ (or O-). If your mom has O+ blood and if you have B- blood, your father could have B-, B+, AB- or AB+ blood.

      It’s not out of the question that your blood types are not what you think they are. It’s wise to have all blood types retested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  98. Cheryl

    I am RH negative and so is my mother. My father is AB positive. I have been told lately it is impossible for him to be my father. Is this correct?
    Cheryl

    Added:
    • Cheryl Greene

      Hi Cheryl,

      Thanks for your question.

      You’ve provided your father’s blood type (AB+) but only your mother and your Rh status (-). With this limited information I can’t address your question fully, but if your mother is Rh- and your father is Rh+, their child could be Rh-. In fact, two Rh+ parents can have a child that is Rh-.

      You mention that your father has type AB blood. If that is the case, he can not have a child with type O blood, but he could have a child with type A, B or AB, depending on the blood type of the mother.

      I hope that’s helpful.
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Cheryl

        My mom and I are both group O RH negative and my dad is AB positive. Is it possible he isn’ t my father. I have been told recently it isn’t possible.

        Added:
        • Cheryl Greene

          Hi again Cheryl,

          Our current understanding of genetics is that it is not possible for one parent to be AB+, the other parent to be O- and their child to be O-. An AB parent can only have children who are A, B or AB.

          It’s not uncommon for blood types to be different than they are thought so it’s wise to have all your blood retested. If there are still questions, a DNA paternity test is the next step.

          I hope that helps.
          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          Added:
  99. Cheryl

    My niece is O negative and she gave birth to an AB+ son. The hospital double cked it at birth, since they say that is impossible. We have many witnesses to the birth!! lol Her husband is AB-. How did that happen?

    Added:
    • Cheryl Greene

      Hi Cheryl,

      Since all blood types have been rechecked, it would be wise to have a DNA paternity (in this case maternity) test run. If the child never left her side in the hospital, this may not be necessary, but it’s still an inexpensive way to double check. If the maternity test comes back that she is indeed the mother, it’s time to look at some very rare blood types that our current ABO testing system can’t detect. This would mean working with physicians and labs that specialize in these rare tests and outcomes and could be quite expensive.

      I hope that’s helpful.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  100. Divya shree

    Hello…. I am divya….my husband blood group is.B+, My blood group is O+, so..my son’s blood group is A+ .How its possible?

    Added:
    • Cheryl Greene

      Hello Divya,

      Our current understanding of genetics is that it is not possible for one parent to be B+, the other parent to be O+ and their child to be O+. A parent with B+ blood and a parent with O+ blood can only have children with B+, B-, O+ or O- blood.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      If you are sure you know who the father is, and if the blood tests still come back with the same outcomes, you might consider looking into a very rare blood type called the Bombay Blood type. Our standard blood tests can not test for this type, so they show up with the wrong blood type. If you’d like to know more about that, please let me know.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  101. Natalija

    Dad:B+
    Mom:A+
    Me:O-
    I don’t know anybody in my family that has Rh- blood bedside me.I’ve read that the chance of this happening is 6,25% and we don’t know my sister’s blood type.Also I know that I am 100% European.
    Can someone please provide me more information about this.

    Added:
    • Cheryl Greene

      Hi Natalija,

      Thanks for writing in.

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O.
      — If a person has type A blood he or she has at least one A allele. He or she can have two A alleles (AA) but can also have one A and one O (AO). Both are called type A blood.
      — If a person has type B blood he or she has at least one B allele. He or she can have two B alleles (BB) but can also have one B and one O (BO). Both are called type B blood.

      Rh+ means a person is positive for the D antigen. Rh- means a person does not have the D antigen.
      — If a person is Rh+, he or she can have a child that is Rh+ or Rh-.
      — If a person is Rh-, he or she can only have a child that is Rh+ if the other parent is Rh+.
      — Two parents with Rh- blood can not have a child with Rh+ blood.
      — Two parents with Rh+ blood can have children with Rh+ or Rh- blood.

      What all this means is if your mom is A+ and if your dad is B+ they could have a child who is O- and that would be perfectly normal. In fact, each of their children has a 6.25% chance of having O- blood.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  102. Rutvi Anil Kalavadiya

    if the parents have a particular blood group.explain why does the children have different blood group

    Added:
    • Cheryl Greene

      Hi Rutvi,

      Thanks for writing in.

      Can you give me an example of each parent’s blood group and the child’s blood group so I will better understand your question?

      Thanks, MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  103. Abdoul

    Hello, I have B, my wife is O . I know we can ha both O or B. My 2 kids are B. so I guess I am BB. My 3rd child is O and I am confused. I can not also be BO and BB. My question is, can 2 parents with B and O have kids with both O and B at the same time?

    Added:
    • Cheryl Greene

      Hello Abdoul,

      Let me see if I’m understanding your question:

      You have blood type B, your wife has blood type O, you have two children with blood type B and one with blood type O. You are wondering if it’s possible that you are the father of all three children.

      If I understand it correctly, the answer is YES! It would mean that you do have one B allele and one O allele in your blood type.

      This outcome is common and totally within reason. In fact, there is a 25% chance each of your children will have blood type O and 75% chance each of your children will have type B blood.

      I hope this is helpful.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  104. Angela

    My sister has always been slightly concerned as to wether she is our full sister. Our mothers blood group is Rh O+ and our fathers is Rh O- ….. me and my youngest sister are Rh O- but our middle sister (who is currently pregnabt) has found out she is Rh OD +….I’ve never heard of this blood group.

    It would mean absolutely nothing if it wasn’t the outcome she wanted..

    But concerns are there and we want to put them to rest.

    Thank you

    Added:
    • Cheryl Greene

      Hi Angela,

      Thanks for writing in.

      It would be interesting to look at the lab reports for all your blood types. Likely they say something like “O+” or “O, D+” or “O, Rh+”. These all mean the same thing. “O+” is just a short way of saying the blood type is O, and the blood is + for the D antigen. It’s called Rh+ because the discovery of the D antigen was made in rhesus monkeys.

      The bottom line is if one parent is O+ and the other is O-, they can have children who are O+ or O-. Your sister’s blood type test doesn’t rule out your father as her biological father. Neither does it prove that he is. Only DNA paternity tests are considered definitive in determining paternity.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  105. Reg

    Question please help. I have been told I have A negative blood. My father for sure has O negative and my mother had O, she has passed so I do not know for sure. My maternal grandfather had A negative. Is it possible that i have A negative with 2 O parents?

    Added:
    • Cheryl Greene

      Reg,

      Thanks for writing in.

      Above you ask if you have A- blood. The easiest thing to do to determine your blood type is to be re-tested by a trusted lab.

      But what I think you’re really asking is “if I have A- blood, my father has O- and I think my mother had type O blood, are they really my parents?” You will likely have a difficult time sussing this all out since your mother is no longer living and you can’t confirm her blood type. But let’s break it down —

      — You could be Rh- even if both parents were / are Rh+, so that’s not an issue.
      — For you to have type A blood, one parent has to be type A or type AB. Since your grandfather is believed to have had type A blood, there is further evidence that your mother could have had type A blood.

      Typically, maternity is easy to prove with photos. There is a very rare occurrence of “switched at birth” scenarios. If you think that is the issue, you could try getting DNA testing from your father since it would be extremely unlikely for him to be the father of two children born in the same hospital on the same day and switched at birth. That would make the record books, I would think.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  106. Christina

    I have B- blood (I have had 2 children, and blood typing for c-sections so I have a card saying I am B-), but both my parent say they are O-. My mother donates blood monthly so I don’t think she is inaccurate. My father has had leukemia, so I don’t think he is inaccurate. Is someone possibly not telling me something?

    Added:
    • Cheryl Greene

      Christina,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for two O- parents to have a B- child.

      If there is a question about paternity (or maternity), a DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      Typically the first step is an open conversation with your parents.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  107. moeby

    Hello, We seem to have some things not adding up.
    Dad O+ , Mom assume AB+, daughter 1-A-, daughter 2-AB+, daughter 3, B+
    we are getting a confirmation on both mom and dad but all daughters are 100% sure and dad 99% sure. how can this be

    Added:
    • Cheryl Greene

      Moeby,

      Thanks for writing in.

      As I’m sure you’ve guessed, if one parent is AB+ and if the other is O+ they can have kids who are A+, A-, B+, B-, O+ or O-. They can not have a child who is AB+ or AB-.

      If there is a question of paternity (or maternity), a DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Lori Rustin

        If kids are now adults and if they were, or are, part of a fairly happy family, does it help anyone to open pandora’s box?

        Added:
        • Cheryl Greene

          Hi Lori,

          Thanks for weighing in.

          You raise a valid point, but there are times when family history provides vital health information. Adult children need to weigh the potential damage that can be done to the family when raising these questions, but there are times for this discovery. Unfortunately, the time is not after a parent has passed away and discovery is no longer a simple DNA paternity test.

          Please let me know what you think.

          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          Added:
  108. David

    Am David, my blood group is O negative and my wife’s blood group is A Positive. Can we have a child?

    Added:
    • Cheryl Greene

      Hi David,

      Sounds like you’ve heard of a condition that can occur when one parent is Rh+ and the other is Rh-. Thankfully for you, there is only a problem when the mother is Rh- and the father is Rh+ and not the other way around.

      Dr. Greene explains it fully in his article How To Determine and Manage Rh Incompatibility.

      To answer your specific question, your two blood types should not be an issue with having children.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  109. Charles

    do both parents have to be O positive cmv negitive for me to have it

    Added:
  110. Arun Kumar A S

    My father and mother has O+ and O- blood group respectively and I have AB+ blood group. Is this possible?

    Added:
    • Cheryl Greene

      Dear Arun,

      Our current understanding of genetics is that it is not possible for one parent to have O+ blood, the other parent to have O- blood and a child their child to have AB+ blood.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought. After repeat blood type tests, if there is a parentage question, a DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  111. Julie

    My blood type is negative A my moms blood type is B positive and my fathers blood type is negative O. Can you please just tell me with a yes or no answer if this is possible? I don’t wanna say anything unless it’s not possible please give me a straight answer

    Added:
    • Cheryl Greene

      Hi Julie,

      First, keep in mind it’s not uncommon for blood types to be different than they are thought. But, our current understanding of genetics is that it is not possible for one parent to be B+, the other parent to be O- and a child their child to be A-.

      It is wise to have all your blood re-tested. If there is a question, a DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Deb

        They are saying a RH positive woman cant have a child with a Rh Negative man and I know this is bs because I have two by an Rh Negative man and I am Rh Positive-it is the other way around-that is what produces a blue baby in the second child if no Rhogam is given to the mother after the first child. Lord what a piece of bs. Rh negative mothers have issues with Rh positive fathers.

        Added:
        • Cheryl Greene

          Deb,

          You are correct, an Rh- mother can have issues if the father of her baby is Rh+. Dr. Greene explains it here — How To Determine and Manage Rh Incompatibility.

          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          Added:
  112. Jeevanajyothi

    I am having A negative blood group while my husband was also having A negative blood group but our baby got B positive. Is it possible

    Added:
    • Cheryl Greene

      Hi Jeevana,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for two parents with A- blood type to have a child with B+ blood type.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  113. Emma

    PLEASE HELP! I’ve been trying to figure this out for a year and no one can give me an answer other than, “Well, that’s just not possible. Did your mom cheat?”
    No, she didn’t…and no one was switched at birth either…Genetic testing proves that.

    Okay: Mom is O+ (100% sure), Dad (we assume) is AB+, Sister is B+ (100% sure), Brother is AB+ (100% sure), and I am O+ (100% sure). How is this possible?

    Added:
    • Cheryl Greene

      Emma,

      Sounds like you’ve done a lot of homework and have heard all the standard answers. A genetic counselor may be able to look at all your tests and provide the answer to your specific situation. There is one very rare combination that could explain it, but I am in no position to say if it applies to you or not.

      The Bombay blood type (0.0004% or about 4 per million in the general population) could fit. In some places such as Mumbai (which was formerly called Bombay) the occurrences can be as high as 0.01% or 1 in 10,000. This group does not fall into the ABO system and the usual tests for ABO blood show them as group O.

      The Bombay blood type is usually only found in small communities where there are other people with the hh blood type. Both parents have to be h carriers, though a parent can be a carrier without actually having Bombay type blood.

      If you suspect you may have the Bombay blood type talk to your doctor about a specialized test for this blood type as it does not show up using the normal ABO blood type tests.

      DNA paternity tests are still accurate (99.999%) with type hh blood and are considered the only accurate test for paternity.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  114. M

    Hello,
    I just found out that I’m O Positive and that my Mother is RH Negative and my dad is A Positive. Is it possible? I wasn’t aware that, could be. Unless I forgot everything I learned in school. Can you please explain?

    Added:
    • Cheryl Greene

      Hi M,

      There are two parts of the common blood types we’re all used to seeing. Part one is A, B, O or AB. Part two is the presence or absence of the D Antigen. That is called Rh+ or Rh-.

      Above you say you are O+. That means you have two O alleles and the presence of the D Antigen. You say your mom is Rh+, but you don’t say what her ABO type is. You also say your dad is A+.

      If either parent is Rh+, i.e. he or she has the D Antigen, each of their children can be Rh+. In your case it doesn’t matter that your mom is Rh-. If your mom is A, B or O you could be O+.

      Please let me know if you have any other questions.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  115. Amalyn

    Hi,
    I am AB neg my husband is O pos, our son is O neg, after everything I read, my understanding is that is that this is not possible. The blood type was confirmed once my son joint the military. Can you possibly have some kind of explanation as to how this is at all possible?
    Thank you in advance for your help and have a blessed day.

    Added:
    • Cheryl Greene

      Amalyn,

      There is a very rare blood type (0.0004% or about 4 per million in the general population) known as the Bombay Blood type. This group does not fall into the ABO system and the usual tests for ABO blood show them as group O.

      The Bombay blood type is usually only found in small communities where there are other people with the hh blood type. Both parents have to be h carriers, though a parent can be a carrier without actually having Bombay type blood.

      If you suspect you or your child may have the Bombay blood type talk to your doctor about a specialized test for this blood type. It does not show up using the normal ABO blood type tests.

      DNA tests are still accurate (99.999%) with type hh blood and are considered the only accurate test for maternity or paternity. If may be easier to have this test done than to pursue Bombay Blood type testing. DNA tests like this one are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  116. Kirti Priya

    My mother has A positive blood group and my father has AB positive blood group. Is it possible for me to have O positive blood group?

    Added:
    • Cheryl Greene

      Hi Kirti,

      Thanks for writing in.

      If one parent has A+ blood and the other parent has AB+ blood each of their children can have A+, A-, B+, B-, AB+ or AB- blood. None of their children can have O+ or O- blood.

      It’s not uncommon for blood types to be different than they are thought. For instance, if one parent is type A+ and the other is B-, their children could be O+ or O-.

      It is wise to have all your blood re-tested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Kirti Priya

        I confirmed the blood groups of my parents. My mother has B positive blood group and my father has AB positive blood group and I have O positive blood group. Could it mean I am adopted?

        Added:
        • Cheryl Greene

          Kirti,

          There is a very rare blood type (0.0004% or about 4 per million in the general population) known as the Bombay Blood type. In some places such as Mumbai (which was formerly called Bombay) the occurrences can be as high as 0.01% or 1 in 10,000. This group does not fall into the ABO system and the usual tests for ABO blood show them as group O.

          The Bombay blood type is usually only found in small communities where there are other people with the hh blood type. Both parents have to be h carriers, though a parent can be a carrier without actually having Bombay type blood.

          If you suspect you may have the Bombay blood type talk to your doctor about a specialized test for this blood type as it does not show up using the normal ABO blood type tests.

          DNA paternity tests are still accurate (99.999%) with type hh blood and are considered the only accurate test for paternity.

          I hope that helps.
          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          Added:
  117. trevor keough

    if both parents are A+, can there child be ARh -Negative. trevor

    Added:
    • Cheryl Greene

      Hi Trevor,

      Thanks for writing in.

      Yes, if both parents are A+, they can have children who are A-. They can also have children who are A+, O+ or O-.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  118. Caitlyn Hixson

    Okay so I’m blood type A+ my ex says he’s either A or B and has a child with another woman who’s and the child is type A+ like me. Mine and his child together is O- what would he have to be to father both children a or b?

    Added:
    • Cheryl Greene

      Hi Caitlyn,

      In your question, you say “…has a child with another woman who’s and the child is type A+ like me.” What is the missing blood type in this sentence?

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  119. Alex E.

    From my understanding, someone who is Rhesus negative does not carry the Rhesus gene. Does that mean they are a “nonprimate humanoid” ?

    Added:
  120. Robert

    Hi Dr.Greene,
    Both parents are O- the child is O+ can this true of the childs blood type?

    Added:
    • Cheryl Greene

      Hi Robert,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for both parents to be O- and their child to be O+. For a child to be Rh+, at least one parent must be Rh+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  121. alan

    can a mother with RHD negative and father who is O + have a baby that is B + ?

    Added:
    • Cheryl Greene

      Hi Alan,

      Thanks for writing in.

      If the mother is RhD- and the father is Rh+, they can have a child that is Rh+. If the mother is type AB or B and the father is type O, their child can have type B blood.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  122. Janice

    This is all very confusing. I know that I’m O- (RH-) and my husband is O+. After the birth of our twins, both who are O+ I was given a RH shot. Our next child is O- or that is what we were told. My daughter-in-law says this is not possible. Is she correct?

    Added:
    • Cheryl Greene

      Hi Janice,

      I agree, this is all very confusing. One of the reasons is the ABO blood groups and Rh factor (-/+) use different rules. You are only concerned about the Rh factor so I’ll address that here.

      If someone is Rh+ he or she is positive for the D antigen. That person may or may not pass it on to his or her children. If neither of the parents have the D antigen present, none of their children can be Rh+. In your case only one parent does have it and can still pass it down, but doesn’t necessarily. That is why the children of one parent who is Rh+ and one parent who is Rh- can have children who are either Rh+ or Rh-.

      I’m so glad you were given Rh shot after your first baby. Dr. Greene writes about How To Determine and Manage Rh Incompatibility. It may be helpful, if you’d like to learn more.

      Thanks for writing in and I hope that helps.

      Best, @MsGreene Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  123. renee

    My father was O+ and my mother was RH-, I am A+, is this correct?? I have always thought I may have been adopted :(

    Added:
    • Cheryl Greene

      Hi Renee,

      Thanks for writing in.

      Blood types can rule out someone as a parent, but they can’t tell you if a specific person is your parent or not.

      In the example you give, you state your father is O+ and you mother was Rh-, but you don’t state if she was O-, A-, B- or AB-.

      What I can tell you from the scenario you provide is if one parent is Rh+ and the other is Rh-, each of their children could be Rh+ or Rh-. Additionally, if both parents are Rh+, each of their children could be Rh+ or Rh-. But if both parents are Rh-, all of their children will be Rh-.

      Bottomline: from the information you have, it’s possible the people who raised you as their daughter are you biological parents, but it’s not proven that they are.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  124. Elaine

    If I am O+ or O- ( can’t remember) & my childs father is O+ can she be A+?

    Added:
    • Cheryl Greene

      Hi Elaine,
      Thanks for writing in.
      If both parent have type O blood, all their children will have type O blood, but if one parent has type O blood and the other has either type A or type AB blood, their children could have type A blood.
      I hope that helps.
      Best, @MsGreene Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  125. Trinity

    If my mother is A+ and father is o+/o- then what can I be?

    Added:
    • Cheryl Greene

      Hi Trinity,

      Thanks for writing in.

      If one parent is A+ and if the other parent is O+/- their child could be A+, A-, O+ or O-. Two Rh+ parents can still have an Rh- child, but two Rh- parents can not have an Rh+ child.

      Please let me know if you’d like further explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  126. Larry Ambrose

    I am Blood Type B Negative. My Wife is also B Negative. We have 4 Children(3 Daughters, 1 Son) . Should(must) all 4 Children have B Negative Type Blood. If not, what are the possibilities of what their Blood Types may be ???

    Added:
    • Cheryl Greene

      Hi Larry,

      Thanks for writing in.

      If both the mother and the father have Rh- blood, that means they do not carry, and therefore can not pass down, the D antigen. They are negative for D Antigen. That means all their children with be Rh-. If both the mother and the father have type B blood, they each have at least one B allele, could also have an O allele. That means it’s possible that each of their children could be B- or O-.

      Please let me know if you’d like more information.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  127. charles

    If child is A or A+ and the mother is B, can a father with type O be the biological father of this mother/child blood type combination?

    Added:
    • Cheryl Greene

      Hi Charles,

      Thanks for writing in.

      If a child is A or A+ and if the mother is B, the father can be A or AB, but not O. If you’d like an explanation please let me know.

      Please remember that blood types are often not what people think they are, so it’s always wise to have blood types retested before making any assumptions.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  128. Julie

    If the mother is A- and the father is A+, can the child be O-?

    Added:
    • Cheryl Greene

      Julie,

      Thanks for writing in.

      It is possible for one parent to be A-, the other parent to be A+ and their child to be O-. In fact there is a 6.25% chance each child will have type O blood and a 25% chance each child will be Rh-.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  129. kay

    I have blood group of B rhesus D positive and also my have the same thing but our first daughter is B rhesus D negative. please help me out

    Added:
    • Cheryl Greene

      Hi Kay,

      There is a bit of information missing from your question. I think you mean both you and your child’s father have B+ blood, but your child has B- and you’d like to know if that’s possible? If that’s what you’re asking, the answer is, yes, that is possible. In fact, there is a 6.35% chance each child of two parents who are Rh+ (or rhesus D positive) will have Rh- (or rhesus D negative) blood.

      I hope that is helpful, but if it’s not, please feel free to reach out again.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  130. Jane

    Hello

    My father was O positive and both my sisters are too, I am AB rhesus negative, so what is mother?

    Added:
    • Cheryl Greene

      Hi Jane,

      Thanks for writing in.

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O.
      — If a person has type A blood he or she has at least one A allele. He or she can have two A alleles (AA) but can also have one A and one O (AO). Both are called type A blood.
      — If a person has type B blood he or she has at least one B allele. He or she can have two B alleles (BB) but can also have one B and one O (BO). Both are called type B blood.
      — If a person has type O blood he or she has two O alleles (OO).
      — If a person has type AB blood he or she has one A allele and one B allele.

      Each person gets one allele from each parent, so IF you have AB blood type, you got an A allele from one parent (type A or AB) and one B alleles from the other parent (B or AB). A person with type AB blood can not have a parent with type O blood, because that person only has O alleles to pass down.

      Before you jump to any conclusions, it’s really wise to have all your blood types retested to be sure. For instance if you have type AB and your father has type B blood, your mother could be A or AB.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  131. Armia

    Is it possible for a child to have different blood type than his parents? My parents are both type O then my blood type is type AB+!

    Added:
    • Cheryl Greene

      Hi Armia,

      Is it possible for a child to have a different blood type than either of his or her parents, unless both parents have type O blood. Here’s the reason:

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O.
      — If a person has type A blood he or she has at least one A allele. He or she can have two A alleles (AA) but can also have one A and one O (AO). Both are called type A blood.
      — If a person has type B blood he or she has at least one B allele. He or she can have two B alleles (BB) but can also have one B and one O (BO). Both are called type B blood.
      — If a person has type O blood he or she has two O alleles (OO).

      Each parent hands one allele down to his or her child. In the case of type O blood, the parent can only hand down an O allele. If both parents have type O blood, each can only hand down an O allele, so each of their children will have type O blood.

      Having said all that, it’s not uncommon for blood types to be different than they are thought and it’s wise to have all your blood retested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  132. Dino

    Hi, I am the father with blood type O- and both my children (Boy and Girl ) is AB + I have read that it is not possible.
    Thanx

    Added:
    • Cheryl Greene

      Dino,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to have type O blood and his or her children to have type AB blood. For a child to have type AB blood one parent must provide an A allele and the other parent provide a B allele. People with type O blood only have O alleles.

      However, it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  133. PRATYUSH SAHOO

    Hello.
    I’M PRATYUSH SAHOO.
    MY father is having O+ve blood and my mother is having B+ve blood.

    And I am having O-ve blood is these RH conditions possible.
    plz help…..

    Added:
    • Cheryl Greene

      Hello Pratyush,

      Thank you for writing in and I understand your concern.

      Yes, it is possible for both parents to have Rh+ blood and their child to have Rh- blood. In fact 6.25% of children with two Rh+ parents have Rh- blood.

      Please let me know if you’d like more details.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  134. Nicki

    Hi Dr Greene,

    My Mother is Rh Negative (A) and my Father is AB Negative. I am A Rh D Positive.
    Is it possible that my father is my biological father if both my parents are a negative and I am a positive?

    Many thanks

    Nicki

    Added:
    • Cheryl Greene

      Hi Nicki,

      Thanks for writing in.

      If both parents are Rh-, they can only have children that are Rh-. Rh+ designates the presence of D Antigen. Rh- designates the absence of D Antigen. If it is not there, it can not be passed down. However, it’s not uncommon for blood types to be different than they are thought. The best next step is to have all three of your blood types retested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Nicki

        Many thanks Ms Greene,
        Some more information has come to light, unfortunately further proving that my Father is not my biological Father. He’s still my Dad though so that’s fine by me. Thanks again for your assistance.

        Kind regards,
        Nicki

        Added:
  135. sandeep

    i am O+ and my wife is A+ can my daughter be B+?

    Added:
    • Cheryl Greene

      Hello Sandeep,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to have A+ blood, the other parent to have O+ blood and their child to have B+ blood.

      It’s not, however, uncommon for blood types to be different than they are thought. It is wise to have all your blood re-tested as a next step.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  136. Abbygale from Philippines

    Hi I’m Abbygale, I had my blood type test and it was resulted in Blood Type A+. My father and my mother was both blood type O. Is that really possible? Additional, some people believe that if you are the first child of your parent, you should have a same blood with your father. Specially if your a girl. Is that true? And is that possible that both Blood Type O parent can have a Blood Type A+ child? Thank you.

    Added:
    • Cheryl Greene

      Hi Abbygale,

      Thanks for writing in.

      It is not true that the first child should have the same blood type as the father — whether you are a male or female.

      Blood types are comprised of genetic material from the mother and the father. If both parents have type O blood, they can only pass down O, which means all their children will have type O blood. If one parent has type A blood and the other has type O, each of their children can be type A or O.

      It’s not uncommon for one parent’s blood type to be different than thought. It is wise to have all your blood re-tested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  137. MJ

    Hi I am O- and my husband is B+ and our son is O+ is this possible?

    Added:
    • Cheryl Greene

      Hi MJ,

      Thanks for writing in.

      Yes, it is possible for one parent to have type O- blood, the other parent to have type B+ blood and their child to have O+ blood. In fact, there is a 25% chance each child from this couple will have type O blood and a 75% chance each child will have Rh+ blood.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  138. Shelly

    I have a question……I am RH O-. I have had 4 children and about 2 years ago was told that I have Trolli (not sure of the spelling) and that I can’t donate blood any more. Can you please explain what this is and how I got it?

    Added:
  139. Claire

    Hi,
    my sister is 0+, her boyfriend is 0-, and their son is A+.
    She told me in private she didn’t have sex with anyone else apart from the father of her son.
    Is there any possible explanation to this?
    Thank you for any help.

    Added:
  140. Glo

    Hello Dr. Greene,
    My Mother and Father both have O- blood. I have O+ blood. Is that possible?

    Added:
    • Cheryl Greene

      Hello Glo,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for both parents to have O- blood and a child their child to have O+ blood. If one parent had O+ blood, and the other had O- blood, it would be possible for their child to have O+ blood.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
    • Ucheime

      Add your message here can parents with O+blood group donate blood to their children with O- negative blood group

      Added:
      • Cheryl Greene

        Ucheime,

        Thanks for writing in.

        In general, a person with blood type O- can only receive O- blood.

        If there is a question about your child needing a blood transfusion, your physician or local hospital can guide you in your specific situation. They will likely retest the family to confirm blood types.

        I hope this is helpful,
        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
  141. RPXS

    Hi,

    My Mother is RH -A
    My Father is RH -O
    My oldest brother is RH -A
    My midle brother is RH -O
    And…
    …I’m the youngest (and I must be the bIack sheep in family) because I’m RH +O.

    I’ve already search that isn’t possible parents with (RH -A) and (RH -O) to have (RH +) positive childrens, can I be a rarely mutation? Or that’s not even possible?

    ps: Im pretty sure they are my parents, because me and my brothers have physical common traces from father and mother.

    Thanks in advance :)
    RPXS

    Added:
  142. Neelu

    When both father and mother has same blood group o positive then they will only conceive famale childs. Why do this happen? I have seen in many cases or every cases I have come across.

    Added:
    • Dr. Alan Greene

      Sometimes when someone flips a coin a few times it comes up the same every time – but with enough results, you’ll see both results. Some families do have all girl children. Some have all boys. But if you know enough different families with two O+ parents, you’ll see. They can have either girls or boys. Best, DrGreene

      Added:
  143. maryann

    i am o postive both of my daughters are rh negative what blood type is the father for them to be rh negative

    Added:
    • Cheryl Greene

      Hi Maryann,

      Thanks for writing in.

      If one parent is Rh+ and the other is Rh-, their children can be either Rh+ or Rh-. Even if both parents are Rh+, their children can be Rh+ or Rh-. That means, if you are Rh+ and if your children are Rh-, their father could be Rh+ or Rh-.

      If you’d like an explanation of how that works, let me know.

      I hope that’s helpful,
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  144. Kara

    Hello Dr,
    Recently I learned that both my mother and father have an O+ blood type and both of my sisters have O+ as well. I am the only child who has B+, my dad is also not listed on my birth certificate and I have a different last name from my mother and father, it is a possibility that I am not related to my mother or father?

    Added:
    • Cheryl Greene

      Hi Kara,

      Thanks for writing in.

      If both parents are O+ their children can be O+ or O-, but not B+. It’s always wise to have blood types re-checked as they are not always what people think they are, either because there was a mixup somewhere along the line or they are remembered incorrectly.

      It sounds like you need to ask your parents about your last name and birth certificate. I would guess that they are anticipating this conversation and just waiting for you to ask.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Kara

        Ms. Greene,
        Thank you for responding back and giving me some more clear answers. Seems as though there are a lot of questions I need answers too.

        Added:
  145. sanu

    My wife blood ab posative my blood group o negative but baby b posative why

    Added:
    • Cheryl Greene

      Sanu,

      Thanks for writing in.

      If one parent is AB+ and the other is O-, it is perfectly normal for their child to be B+. The child would get a B allele and positive antigen from the AB+ parent and an O allele and negative antigen from the other parent, but that is called B+.

      Let me know if you’d like more explanation.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  146. Debbie

    If my Mother is AB- and my Father is O+ how can I be AB-. Wouldn’t this mean that my Father is not my real Father? I have the RH factor and I think my Mother did 2. She is no longer alive and my Father will do not do testing so I think he knows he I may not be his. Sad!

    Added:
    • Cheryl Greene

      Hi Debbie,

      I’m so sorry to hear of your upsetting situation.

      For a child to be AB-, she has to get an A from one parent and a B from the other. A person with type O blood can not hand down either an A or a B. A child can have Rh- blood even if one or both parents are Rh+, so that is not an issue in your situation.

      Often blood types are not what they are thought to be, so there is a chance that all three blood types do fit together. Since your mother is no longer living, she can not be tested. Since your father is unwilling to be tested, he can not be tested. But you could consider checking on your blood type. If you were type A or B, you could have a mother who is AB and a father who is type O.

      Sorry I couldn’t be more helpful.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Ayla G.

        How about if the father with O type is A Bombay blood type,
        I think it is possible, If the father with blood type has A or B without antigens, test shows him as O blood type, but in reality He might be A or B in his genes.

        Added:
  147. tricia

    I am AB+ (confirmed by reliable sources), my mother is A+(confirmed as well) , and my father is O+ (Confirmed). Is this possible?

    Added:
  148. Butler Carolyn

    I have Rh A negative blood.
    Both my parents have o positive.
    Or so I have been told. I have breast cancer and before anything happens I would love to get answers. Is this my father? He has passed now and I am older but need closure.

    Added:
    • Cheryl Greene

      Carolyn,

      I’m so sorry you have breast cancer. I had metastatic, triple negative, inflammatory breast cancer 21 years ago. That’s an aggressive cancer, but I’m here today, which I hope is an encouragement to others.

      You are correct that two O+ parents can not have a child who is A-. You are in a tough position. Since your father has passed away, you can not confirm his blood type. Sadly, blood types are often different than people think they are. This can happen because there was a lab error, a reporting error or inaccurate memory.

      So for instance, if both parents are O+, they could have a child that’s O+ or O-. Or if one parent was A+ and the other was O+, they could have a child who is O+, O-, A+ or A-.

      If your father was still living there are inexpensive DNA tests that are 99.99% accurate. If this is terrible important to you and you have some samples of his DNA (root of a hair for instance) there are expensive ways to have DNA tests run, but I’m afraid I don’t have information about them.

      I wish I could offer you the closure you’re looking for, but I’m afraid I can not.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  149. Vijaya

    we both are O positive blood group but I dont understand how come my baby blood group is AB positive.
    Please advise me is this possible?

    Added:
  150. Lea

    My father is B+ and my Mum is O and my brother and sister have B+. And I am having an O blood type, is this possible?

    Added:
    • Cheryl Greene

      HI Lea,

      Thanks for writing in.

      Yes, it is possible for one parent to have B+ blood, the other to have O blood, and to have one child who has B+ blood and another who has O blood type. If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  151. Heathee

    Hi I’m 39 an have a daughter that is 23 an I am RH- an so is she.. I was wondering what blood type would her father most likely be for her to end up with my blood type an if a paternity yes would show negative on him due to my blood type

    Added:
  152. David

    My blood type is AB- and my sons mother is O-. Both of us have had our blood type tested many times. My son is B+. Is this a normal occurance?

    Added:
  153. jane

    Hi. I have AB Blood, my sisters all have O,, I had my mother health records yrs. ago but lost them but I am sure she was an O.. where did I COME FROM…WAS SHE MY MOTHER ???

    Added:
    • Cheryl Greene

      Hi Jane,

      Thanks for writing in.

      Unfortunately, you may never know for sure, but I can tell you there are several combinations of parents’ blood types that can result in their child having type AB blood. The only blood type that can not have an AB child is type O.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  154. Arthur King

    Hi, My blood type is O+, my child mother blood type is O+, is it possible for the child to have an A+ blood type?? Kindly provide an urgent response.

    Added:
    • Cheryl Greene

      Dear Author,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for two parents with O+ blood to have a child with A+ blood.

      It is wise to have all your blood re-tested. It’s not uncommon for blood types to be different than they are thought.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  155. Kathy

    Hi, I’m wondering why I have blood type ‘O’, despite my mother having blood type ‘O’ and my dad having blood type ‘AB’. Isn’t this impossible?

    Added:
    • Cheryl Greene

      Hi Kathy,

      Thanks for writing in.

      Typically this would indicate that either the blood types are not what you think they are (i.e. you are not type O or your father is not type AB) or the man you call father is not your biological father. There is however a very rare blood type (0.0004% or about 4 per million in the general population) known as the Bombay Blood type. In some places such as Mumbai (which was formerly called Bombay) the occurrences can be as high as 0.01% or 1 in 10,000. This group does not fall into the ABO system and the usual tests for ABO blood show them as group O.

      The Bombay blood type is usually only found in small communities where there are other people with the hh blood type. Both parents have to be h carriers, though a parent can be a carrier without actually having Bombay type blood.

      If you suspect you may have the Bombay blood type talk to your doctor about a specialized test for this blood type as it does not show up using the normal ABO blood type tests.

      DNA paternity tests are still accurate (99.999%) with type hh blood and are considered the only accurate test for paternity.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Kathy

        Thank you very much for replying, Ms Greene. Well, I asked both of my parents whether they are sure their blood types are correct and they were positive. I’m still not convinced, though, as they might be wrong too! There could be a misdiagnosis while deciding their blood types.

        I have another question though, is it possible for a person with blood type O to have a child with a person with blood type AB? What will happen their child?

        Added:
        • Cheryl Greene

          Hi Kathy,

          There are no special problems related to blood types if one parent is type O and the other parent is type AB, unless the mother is Rh- and the father is Rh+. For more information on that, you can read Dr. Greene’s article How To Determine and Manage Rh Incompatibility.

          Also, it is very common for blood types to be different than people think they are. It’s really worth getting retested if there’s any question.

          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          Added:
          • Varun

            Both parents has 0+ blood group and baby has A+. Is this normal? Or father is not biological father?

            Added:
          • Cheryl Greene

            Hi Varun,

            Thanks for writing in.

            According to our current understanding of science, if both parents have O+ blood, their children can only be O+ or O-.

            It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

            I hope that helps.
            Best, @MsGreene
            Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

            Added:
        • Jasmine

          i have a question me and my brother both have o- blood and so does my mom but my dad has ab blood and i was just told by my health teacher that was impossible for that to happen…..and i look like my dads mini me basically…..am i being told my dad isnt really my dad?

          Added:
          • Cheryl Greene

            Hi Jasmine,

            Thanks so much for writing in.

            Our current understanding of genetics is that it is not possible for both parents to have type O blood and their child to have AB blood. An AB parent can only have children who are A, B or AB.

            However, it’s not uncommon for blood types to be different than they are thought so it’s is wise to have all your blood retested.

            If there is still a question, a DNA paternity test is the only test considered definitive. They are considered 99.999% accurate.

            I hope that helps.
            Best, @MsGreene
            Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

            Added:
  156. Christina

    I have long wondered if I may be adopted. My mother was A+ and my father was B+. I am AB-. What little I know about genetics suggests that either one or both of my parents (they were truly lovely people) was not my biological parent.

    Added:
    • Cheryl Greene

      Hi Christina,

      Thanks for writing in.

      As it turns out, if one parent is A+ and if the other is B+, it is completely normal for their child to be AB-. If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  157. J

    hello , i have a question. if i am A+ and my partner is B+ is it possible that my antibody screening can come back positive for pregnancy?

    Added:
  158. Shade trapiana

    Hi mother is o+ and dad is A+. The baby is A- what are the odds of that.

    Added:
    • Cheryl Greene

      Hi Shade,

      Thanks for writing in.

      If one parent has O+ blood and if the other has A+ blood, the chance that each of their children has type A blood is 75%. The chance that each of their children is Rh- is 6.25%.

      I hope that’s helpful,
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  159. Ceyana Briggs

    Hi I am O positive and my husband is B negative. Is it possible to have a baby with O positive blood type?

    Added:
    • Cheryl Greene

      Ceyana,

      Thanks for writing in.

      Yes, it is possible for one parent to be O+, the other parent to be B- and their child to be O+. If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene.

      Added:
  160. MWJ

    If one parents are O Negative the other the O positive can you get a baby born with a B blood type

    Added:
    • Cheryl Greene

      Hi MWJ,

      Thanks for writing in.

      Our current understanding of genetics, is if both parents have type O blood, their children can ONLY have type O blood.

      It is so common for people to think they have one blood type and actually have a different one, that doctors always check for blood type before they give someone blood. It is wise to have all three types retested before jumping to any conclusions.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  161. May.H

    My mom is AB positive, my dad is 0 negative, I’m 0 negative,my brother is 0 negative, my sister is O positive, does that mean our sister is not from one of our biological parents? We all have had childern and our blood has been tested because of the RH factor negative. Being O negative. Thank you, I hope you can help both my brother and I we have wondered about this for manys years and have not said anything to our sister. Your Sincerely

    Added:
    • Cheryl Greene

      Hi May,

      Thanks for writing in.

      Has your mom’s blood type been confirmed as AB+? I ask because, according to our current understanding of science, a parent with AB blood can not have a child with type O blood.

      On the other hand:
      — If one parent is Rh+ and the other is Rh-, they can have children who are Rh+ or Rh-.
      — If both parents are Rh+, they can have children who are Rh+ or Rh-.
      — If both parents are Rh-, they can only have children who are Rh-. They can not have children who are Rh+.

      I hope that’s helpful.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  162. J King

    One parent the mother is At and the alleged father is A-. What blood type will the baby be?

    Added:
    • Cheryl Greene

      Hi J,

      Thanks for writing in.

      If one parent is A+ and if the other parent is A-, each of their children could be A+, A-, O+ or O-.

      Please let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  163. Kaiti

    My mom is A positive, my dad is B positive, but I’m 0 negative, does that mean one (or both) are not my biological parents?

    Added:
    • Cheryl Greene

      Hi Kaiti,

      Thanks for writing in.

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O.
      — If a person has type A blood he or she has at least one A allele. He or she can have two A alleles (AA) but can also have one A and one O (AO). Both are called type A blood.
      — If a person has type B+ blood he or she has at least one B allele. He or she can have two B alleles (BB) but can also have one B and one O (BO). Both are called type B blood.

      Rh+ means a person is positive for the D antigen. Rh- means a person does not have the D antigen.
      — If a person is Rh+, he or she can have a child that is Rh+ or Rh-.
      — If a person is Rh-, he or she can only have a child that is Rh+ if the other parent is Rh+.
      — Two parents with Rh- blood can not have a child with Rh+ blood.
      — Two parents with Rh+ blood can have children with Rh+ or Rh- blood.

      What all this means is if your mom is A+ and if your dad is B+ they could have a child who is O- and that would be perfectly normal.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  164. Robin

    I am O+, my husband A+. My oldest is A+ and youngest daughter A-. This is possible correct? My youngest daughter is worried cause she is A-. We have a son, as well, but his blood type unknown.

    Added:
    • Cheryl Greene

      Hi Robin,

      Thanks for writing in.

      If one parent is O+ and if the other parent is A+, there is a 75% chance each of their children will have type A blood and a 6.25% chance each of their children will be Rh-.

      If you’d like an explanation, let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  165. Cecilia

    Hi! I have been thinking for some time if I am really be my parent’s daughter. I could have been switched at birth. My mother and father have AB+ blood and O blood type respectively. I got O+ type, could they not really my biological parents?

    Added:
    • Cheryl Greene

      Cecilia,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to be AB+, the other parent to be O and their child to be O+. An AB parent can only have children who are A, B or AB (depending on the blood type of the other parent).

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  166. dancerdancer42

    Hi. I have the rarest blood type, AB-. My mom has A+, and my dad has O+. I personally think I could’ve been switched at birth. My mom denies it every time I ask her/when I try to tell her that it’s possible. I found out my dads and my moms by saying that I needed to know their blood types because of a school project. I know lying is wrong, but when my mom refuses to think that it could be possible, she hears what she wants. My dad and my sister believe that it could be possible. When I brought it up at the dinner table once, my dad told me that when I was born, the doctors couldn’t give me back to my mom right away because of a mix up with the bracelets that we were wearing. Seems a little weird. Is there anyway that I could be my parents daughter, despite the blood type differences?

    Added:
    • Cheryl Greene

      Dear Dancer,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to be A+, the other parent to be O+ and their child to be AB-. That said, it’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested before jumping to any conclusions.

      If there is a question, a DNA paternity test is the only test considered definitive to establish paternity or maternity. The tests are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  167. Sandy

    Hi
    Father is A+ Mother negative first 3 children are A+ child 4 RH-2 So is father the father of #4? And has anyone made a connection with RH- children not getting the normal childhood diseases. Like chicken pox, missals, ect. Thank you

    Added:
    • Cheryl Greene

      Hi Sandy,

      Thanks for writing in.

      If one parent is A+ and if the other parent is A-, each of their children could be A+, A-, O+ or O-. Does that answer your question?

      I am unfamiliar with a link between Rh- blood and extra immunity to normal childhood diseases.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  168. brenda owens

    hi I have a positive blood my mom is rh negative my dad a positive its been said my dad cannot be my bio father is this blood type not possible

    Added:
    • Cheryl Greene

      Hi Brenda,

      Thanks for writing in.

      If one parent has Rh- blood and the other has Rh+ blood, each of their children can be Rh+ or Rh-.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  169. Tia

    Hi, I have a question, my blood group is A+, my mum is O-, and my dad is B-, is it possible my dad may not be my dad.

    Added:
    • Alexandra Carmichael

      Hi Tia,
      Thanks so much for writing in! Our current understanding of genetics is that it is not possible for one parent to be B-, the other parent to be O- and their child to be A+. An B parent can only have children who are B or O.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Alexandra (caring helper at DrGreene.com, not a doctor)

      Added:
  170. Sarah

    I have a question; my mom has A Positive blood and my dad has B Positive blood. My older brother and I both have AB Negative blood. What are the chances of such an occurrence?

    Added:
    • Cheryl Greene

      Hi Sarah,

      Thanks for writing in.

      If one of your parents is A+ and the other is B+, there is a 56.25% chance each of their children will be AB and a 6.25% chance each child will be Rh-. The odds are the same for each child, so the fact that you are both the same are not unexpected, but still very cool.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  171. Akib

    Can O father have a child AB…I am not sure about mother…Is there any chances of AB child…any mutation effects or its impossible

    Added:
    • Cheryl Greene

      Akib,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to be O, and their child to be AB.

      It is wise to have both your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  172. G SARAN

    IN IVF MY BLOOD IS A POSITIVE AND MY HUSBAND BLOOD IS O POSITIVE HOW MY BABY AB NEGATIVE

    Added:
    • Cheryl Greene

      Thanks for writing in.

      The testing during IVF if extensive. I’m not a physician, but if this were me, I’d ask the IVF doctor to explain. He or she may want to retest to confirm all blood types.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  173. Ali

    My Blood group is O+ and my wife has B+ but son has A+ , what does it means

    Added:
    • Cheryl Greene

      Ali,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to be O+, the other parent to be B+ and their child to be A+. If one parent is B+ and the other parent is A+, A-, AB+ or AB-, it would be possible to have a child who is A+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  174. Michaela

    Both my parents have O positive and while I have AB positive

    Added:
    • Cheryl Greene

      Hi Michaela,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for both parents to be O+ and their child to be AB+. Two O+ parents can only have children who are O+ or O-.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • geetha

        Father O+ mother b+ but child AB+ is possible

        Added:
  175. Trina

    Baby is O+ . Father is O- and I am B- is that possible

    Added:
    • Cheryl Greene

      Hi Trina,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for both parents to be Rh- and and their child to be Rh+. It is possible for one parent to be type O, the other to be type B and their child to be type O.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  176. SAHIL SHARMA

    HELLO,
    MYSELF SAHIL. I HAVE 4 KIDS.MY BLOOD GROUP IS A+ AND MY WIFE BLOOD GROUP IS A+.
    TWO OF OUR KIDS BLOOD GROUP ONE IS B+ AND ANOTHER IS AB+ .
    AS PER ABOVE CAN YOU PLEASE HELP ME KNOW THAT IS IT POSSIBLE.

    REGARDS

    Added:
    • Cheryl Greene

      Dear Sahil,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for both parents to be A+ and their child to be B+ or AB+. If two parents are A+ each of their children can be A+, A-, O+ or O-.

      However if one parent is A and the other is B or AB, and if at least one or both of the parents have Rh+ blood, they could have children who are A+, B+ or AB+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  177. Tosbrawn

    hello Dr Greene.

    pls am B Rh D positive and my wife is B Rh D negetive but my son is O Rh D positive could that be possible.

    Added:
    • Cheryl Greene

      Toshbrawn,

      Thanks for writing in,

      Yes, it is possible for one parent to be B Rh D positive and the other to be B Rh D negative and their child to be O Rh D positive.

      When the mother is positive and the baby is negative, their can be incompatibility issues and the mother needs treatment before having any additional children. Has your wife had treatment?

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  178. Molly

    Hi, my blood type is O+, my fiancé blood type is O+ and my son’s blood type is O+. What are the probabilities of my fiancé being the father to my son in terms of percentage. Thanks

    Added:
  179. rajib das

    sir i am A + and my wife is A- but our baby is O+ is it possible
    or other way i.e my wife is sex with other person who is O+

    Added:
    • Cheryl Greene

      Rajib,

      Thanks for writing in.

      It is completely normal for one parent to be A+, the other to be A- and their child to be O+.

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O. Each person also has the presence of D antigen (which we call Rh+) or the absence of D antigen (which we call Rh-).

      — If a person has type A blood, he or she has at least one A allele (this can be AA or AO).

      — If a person has type O blood, he or she has two O alleles (OO).

      This means if your blood type is A+ and the mother of your baby’s blood type is A-, each of you would have passed an O allele down to your child.

      Additionally, if your wife is A- and if you are A+, the Rh+ would have come from you and could not have come from her. This leads to a much bigger issue and one I’m sure your doctor has addressed. The two of you have blood type incompatibility and she must be treated before you have a second child. If this has not been addressed, bring it up with her physician immediately.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  180. Cara

    Hi! I was just wondering. I am O-/RH- and my husband is O+. We have two children, a boy and a girl. Would it be more likely for them to have RH- since I have it? (Sounds odd saying I have something that technically says negative, as in none- lol)
    I know my father wasn’t RH- but my mother was.

    Added:
    • Cheryl Greene

      Hi Cara,

      Thanks for writing in.

      If one parent is O- and the other is O+ there is only a 6.25% chance that each of their children will be Rh- and a 93.75% chance each child will be Rh+. There is a 100% chance each will child will have type O blood.

      It doesn’t matter which parent has Rh+ and which parent has Rh- blood.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  181. Yna

    My husband is type O+and me is type B+ it is possible to get a baby type A+

    Added:
    • Cheryl Greene

      Yna,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to be B+, the other parent to be O+ and their child to be A+. These two parents could only have children that are B+, B-, O+ or O-.

      It is wise to have all your blood re-tested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  182. Jenny

    Great stuff above, Question: from my 30 year old daughter, supposedly two parents who are O negative have an A negative baby (30 year old ) is this a mutation ? She is the first the others are all O negative ?

    Added:
    • Cheryl Greene

      Hi Jenny,

      Thanks for writing in.

      If both parents are O-, their children can only be O-.

      My guess is either one of the three blood types isn’t what people think it is or there is a different father for the first child. DNA paternity tests are 99.999% accurate.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
    • geetha

      B+&O+ to be matching AB+ is possible to match

      Added:
      • Cheryl Greene

        Geetha,

        Thanks for writing in.

        Our current understanding of genetics is that it is not possible for one parent to be B+, the other parent to be O+ and their child to be AB+.

        It is wise to have all blood retested. It’s not uncommon for blood types to be different than they are thought.

        I hope that helps.
        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
      • maya

        Father O+ mother b+ child A1b+ is possible

        Added:
  183. georgina

    If my mum is B+ and my dad is A+ what am i?

    Added:
    • Cheryl Greene

      Hi Georgina,

      Thanks for writing in.

      If your mom is B+ and your dad is A+, you are in a unique situation. With those two types you could be any blood type. This is the only parental combination that can combine to make any blood type.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  184. Shaaz

    Can a child have B+ blood group if both his/her parents are O+ ?

    Added:
    • Cheryl Greene

      Dear Shaaz,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for two parents with O+ blood to have a child with B+ blood. Two parents with O+ blood can only have children with O+ or O- blood.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  185. natasha

    Hello,
    I would like to know what my dad’s blood would be as i am B+ and my mom think she is O, don’t know which one – or + so I would be appericate if could you give me an answer what possiblity and impoosible to have? as i know my sister is O- so i have more siblings as they dont know what their are.
    thank
    Natasha

    Added:
    • Cheryl Greene

      Hi Natasha,

      Thanks for writing in.

      If your mom has type O blood and you have and if you’re B+ and if your full sibling is O-, then your father could only be B+ or B-. We know this because you had to get at least one B allele and you could not get it from your mother. We know he could not be type AB because if he was, your full sibling could not be type O.

      If you are are Rh+ then one of your parents must be Rh+. Both can be Rh+ and your sister could still be Rh-, so that doesn’t help narrow down whether your father is Rh+ or Rh-.

      All of this assumes that you are correct in your blood type and the blood types of your mom and your sister.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  186. Luis

    Hi! If my wife is o+ and my 3 kids are o+,B+ and A+ ……. What would mine be?

    Added:
    • Cheryl Greene

      Hi Luis,

      Thanks for writing in .

      According to our best understanding of current science, if the mother of your children has type O+ blood, there is no blood type you could have that would allow you to have one child who is type O+, one that is type B+ and one that is type A+.

      If on the other hand, if one parent is type A and the other parent is type B, the two parents could have one child who is type O+, one that is type B+ and one that is type A+, if at least one of the two parents was Rh+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  187. Nikhil

    If my parents have B+ and B- blood types, then is it possible for me to have AB+ blood type?

    Added:
    • Cheryl Greene

      Hi Nikhil,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to be B-, the other parent to be B+ and their child to be AB+. Two B parents can only have children who are B or O. If one or both parents is Rh+ their children can be Rh+ or Rh-.

      It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  188. Tracy

    Hi, I have a question please.
    My mother is type B+ and my father is type O+.
    Both my sister and I are AB+.
    The results are correct as we have all been tested several times.
    Are you able to say how this has occurred, and possibly give some explanations please?
    Thank you

    Added:
    • Cheryl Greene

      Tracy,

      That’s a great question.

      There is a very rare blood type (0.0004% or about 4 per million in the general population) known as the Bombay Blood type. In some places such as Mumbai (which was formerly called Bombay) the occurrences can be as high as 0.01% or 1 in 10,000. This group does not fall into the ABO system and the usual tests for ABO blood show them as group O even though they are hh. This could be your father’s type and could explain why the tests say he’s type O.

      If you suspect you father may have the Bombay blood type talk to your doctor about a specialized test for this blood type as it does not show up using the normal ABO blood type tests.

      DNA paternity tests are still accurate (99.999%) with type hh blood and are considered the only accurate test for paternity.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  189. Emelyn

    Hi i found out that my baby is +b blood type and im +O and im asking the father of my child he said he is sure that he is +O as well.
    Is it possible to have a +B baby with both parents are +O?
    My baby is sick with metabolic disorder,horshoe kidney,renal failure.
    Your answe will be a big help.
    Thank you

    Added:
    • Cheryl Greene

      Emelyn,

      I’m so sorry to hear that your child is so sick. That must be heart breaking.

      Our current understanding of genetics is that it is not possible for both parents to have O+ blood, and their child to have B+ blood. Two O+ parents can only have children who are O+ or O-.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  190. Florence

    Hi, my Mum was A+ and Dad was O+ is it possible that my blood is A-? Thanks!

    Added:
    • Cheryl Greene

      Hi Florence,

      Thanks for writing in.

      Yes, if your mum’s blood type was A+ and your dad’s blood type was O+, you could be A-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Sb

        Hi I’ve been trying to figure out my blood type for years. My daughters are B positive and O positive. My mom is A positive and my dad is O not sure positive or negative. I can’t donate blood due to small veins and my dr won’t do the test due to cost. My mom believes I’m O but doesn’t know positive or negative. Can you help?

        Added:
        • Cheryl Greene

          Sb,

          Thanks for writing in. It’s hard to determine blood types without tests, but here’s what we know.

          If your mom is A+ and if your dad is O + or O-, you could be A+, A-, O+ or O-.

          Your daughter would have gotten the B from her father. If your children’s father is Rh-, you are Rh+.

          That’s all we know for sure for the information you’ve provided.

          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          Added:
        • L. S.

          Sb, just so you know, most blood banks will test your blood type when you give at no cost to you. I can only go from my experience from the state in which I live and that my donations went through the Red Cross. If you truly want to give blood, I’d suggest that you check with the Red Cross where you live.

          Added:
  191. Paula

    I have 3 siblings one blood type O NEG and 2 A POS mine is A neg would we have the same parents?

    Added:
    • Cheryl Greene

      Hi Paula,

      Thanks for writing in.

      The short answer is yes, you could have the same parents. If one of your parents had type A blood and the other had A, O or B and one or both of your parents were Rh+, you could all be full siblings.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  192. Jordyn Miller

    My mother has A+ blood and my father has O- blood. How is it possible for me to be AB+?

    Added:
    • Cheryl Greene

      Hi Jordyn,

      Thanks for writing in.

      Our current understanding of genetics is that it is not possible for one parent to be A+, the other parent to be O- and their child to be AB+. A parent with type O blood can not have a child that is type AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  193. Sruthi

    Am B negative , my mother is O positive & Dad is B positive how can I be B negative?

    Added:
  194. Ronald Chriscoe

    If my mother an father are A+ is it possible to make a O+ baby?

    Added:
    • Alexandra Carmichael

      Hi Ronald,
      Thanks for writing in! Our current understanding of genetics is that it is not possible for both parents to be A and their child to be O. It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

      Added:
    • Dr.Safia

      Yes. It is possible for parents who are AO (i.e. A+ or A-) and AO (A+) to have kids that are either AA (A+) , AO (A+) or OO (O+).

      Added:
  195. S crockett

    Out of all my siblings their all a and b blood why am I rh have to get a shot while pregnant

    Added:
  196. Lawanda Lindsey

    My parents are both o positive and my sister is A negative. I am Ab negative so how is that possible

    Added:
    • Alexandra Carmichael

      Hi Lawanda,
      Thanks so much for writing in! Our current understanding of genetics is that it is not possible for both parents to be O and the kids to be A and AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

      Added:
      • Marcia

        Hi, if both my parents are A+ why my blood type turned out to be A-.

        Added:
        • Alexandra Carmichael

          Hi Marcia,
          Both your parents could be carriers of Rh-, even though they show up as positive, so it’s possible they both passed the negative allele to you.
          Hope that helps!
          Alexandra (caring helper at drgreene.com, not a doctor)

          Added:
  197. Thomas Rendleman

    Is it possible for an O Neg and an AB+ to still have O Neg children. The AB+ doesn’t have RH Neg in family.

    Added:
  198. Swathi

    Hello Dr,
    What will be the blood group of the child of parents having blood group A+ and B-

    Added:
  199. Kayla

    Im A+ is it possible to have a parent o- and o+

    Added:
    • Alexandra Carmichael

      Hi Kayla,
      Thanks for writing in! Our current understanding of genetics is that it is not possible for one parent to be O-, the other parent to be O+ and their child to be A+. One parent would have to be A or AB to have an A child.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

      Added:
  200. Khalid

    Hello dr.

    I need your kindly help , I am (A+), and my wife is (AB+), and my daughter ( A-) !?
    1- Is it possible to have a child with (A-)blood , while I’m (A+) and my wife (AB+) ?
    And what is the possibility of the child blood groups with their RH -+ in our case ?

    Thanks in advance for your help and appreciate your soonest reply .

    Regards,

    Added:
  201. Lia

    Hi Dr. Greene,

    I was wondering about my blood type since it is different with my parents. My blood type is A+, while my father is O+ and my mother is B+. I was searching about this but couldn’t find the right answer yet.

    For your information, all of my father’s family’s blood type is O+, and my mother’s parents are O+ and B+. I have a younger sister which blood type is B+.

    Can you please explain why my blood type is different with them?

    Your answer will be very helpful to me. Thank you :)

    Added:
    • Alexandra Carmichael

      Hi Lia,
      Thanks so much for writing in! Our current understanding of genetics is that it is not possible for one parent to be O, the other parent to be B and their child to be A.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

      Added:
      • Mary

        I am O+ and my husband is A+. Is it possible to have a O- child?

        Added:
        • Alexandra Carmichael

          Yes, this is possible. You could both be carriers of the Rh- allele, and then it could be passed on to your child.
          Hope that helps!
          Alexandra (caring helper at drgreene.com, not a doctor)

          Added:
  202. Alex

    My father’s blood group is B+ and my mother’s blood group is O+
    …I have a elder brother with O+ blood type
    ….but I am AB+….I have read on many websites it is impossible for me to have AB+.Can someone please explain me how/why?

    Added:
    • Alexandra Carmichael

      Hi Alex,
      Thanks so much for writing in! Our current understanding of genetics is that it is not possible for one parent to be O, the other parent to be B and their child to be AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.
      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

      Added:
  203. Kate

    Both my husband and I are 0+, but one of our sons is AB-, which I have been told is rare.
    We weren’t told of his blood type at the time of birth, we found out later. I did have the Rhesus injection a day or so after his birth.
    I’ve been told that this is impossible. When I discussed it with our family doctor, he told me ‘not to go there’

    Added:
    • Cheryl Greene

      Kate,

      How tough. You are right, this doesn’t match our medical understanding, but there are a couple of issues.

      1) If you are Rh+ you do not need the Rhesus injection. A couple of options — either you are not the blood type you think you are, you got a different injection, or it was given to you in error.

      2) If both parents are O+ and if the baby is AB-, neither parent is the biological parent.

      Your options include having all blood re-tested, DNA paternity / maternity tests, and “not going there”.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  204. Mo

    Hi, my ex husband and I are both Rh B positive, my eldest daughter is Rh D negative, is this possible?

    Added:
    • Maureen

      My husband and I are both b.pls, my daughter is rh d negative, is this normal.

      Added:
      • Cheryl Greene

        Hi Maureen,

        Yes, it is normal for two parents with Rh+ blood to have a child with Rh- blood.

        If you’d like an explanation, please let me know.

        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
    • Alexandra Carmichael

      Hi Mo,
      Thanks so much for writing in! If your question is whether two Rh+ parents can have an Rh- child, the answer is yes if the parents are both Rh+- (there are two alleles, or forms, of the Rh gene that every person carries, and + is dominant, but if you both carry the – allele as well, it’s possible you could have both passed it on to her and she would present as Rh-).

      Hope that helps!
      Alexandra (caring helper at drgreene.com, not a doctor)

      Added:
  205. MJ

    Hi im 47 and resus neg blood both my parents are o positive iv been told one of them may not be my parent as this isnt possible ?? Im very confused pls help x

    Added:
  206. Therese

    Hi, my mother has A+ blood while my father has A- I also have A- blood, however, my brother has AB+ blood. My grandmother (mother’s side) has got AB+ blood if that makes a difference, all information about blood type inheritance I have come across says that A and A cannot =AB. Our blood types have been reconfirmed, do you think this is simply a mutation or that something else is to blame?

    Added:
    • Cheryl Greene

      Therese,

      Our current understanding of genetics is that it is not possible for one parent to be A-, the other parent to be A+ and a child their child to be AB+. Two A parents can only have children who are A or O.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought. It sounds like you may have already retested. If so, consider a DNA paternity test. They are considered 99.999% accurate and will answer the question of mutation or “something else to blame”.

      Here’s a like to a simple home DNA test that can provide the information you are looking for while maintaining your privacy.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  207. Mary

    Hi,
    I am a mother with O+ & both my boys are O-. What would the father’s blood type have to be for this to occur?

    Added:
    • Cheryl Greene

      Mary,

      If your blood type is O+ and your son’s are O-, their father could be O+, O-, A+, A-, B+, B-, but could not be AB+ or AB-.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  208. Lisa

    Hello,

    I am O+ and my boyfriend is O-
    We all retested our blood types and two totally different hospitals have indicated that our son is B+. He was with me from the day of his birth until the day of discharge. We even had matching security arm bands to prevent a mix up. My son is now five years old and I’m too scared to even think that he is not mine.
    Is his blood type possible?

    Added:
  209. Teena

    Hai doctor,
    I am Teena my age is 41 my blood group B+ve and my husband B-ve and my son O-ve if possible different blood group 3 of us?I heard about that its very complicated to get 2nd baby I want 1 more baby what i can do?please reply me?

    Added:
    • Cheryl Greene

      Hi Teena,

      If your blood type is B+ and your son’s father’s type group is B-, your son’s blood type can be O-.

      If the mother’s blood is Rh- and the father’s is Rh+, there can be difficulties with subsequent pregnancies. There is no issue if the mother is Rh+ and the father is Rh-.

      If you’d like further explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  210. AMSIS

    my mother is B+, my father is A+, I am B+, and two of my brothers are AB+ and A+ respectively. However, one of my brothers is O- and also has green eyes when we all have blue eyes. Is his blood group possible with the family blood grouping

    Added:
    • Cheryl Greene

      Amsis,

      Yes, if your mother is B+ and your father is A+, your siblings can be O-, AB+, A+ and B+.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  211. shalini

    Hello dr.green,
    My husband and I are B +. We have our elder daughter with B- and younger daughter with O-. Is there anything that I should be concerned about in future? Can you please explain on this.

    Added:
  212. Divyanshi kapoor

    My father is B+ and my mother is O+. I am B-. Is this normal?

    Added:
    • Cheryl Greene

      Divyanshi,

      Yes, this is perfectly normal. If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  213. Mary

    Can an o- parent and a o+ parent have a child with rh blood?

    Added:
  214. Billy

    If the father is Type O+ and the mother RH- can the baby be A type

    Added:
    • Billy

      If the father is Type O + and the mother is RH- can the baby be A

      Added:
  215. Debra Gaynor

    My mother is O- and my father is A+ but my blood type is B+. I have been tested more than once and so has my mother plus my dad has donated blood more than once and was tested by the Red Cross. Can a mother with O- and a father with A+ have a child with B+?

    Added:
  216. biswajit

    I am b positive and my wife is o positive. My daughter has o negative blood group. Is it possible?

    Added:
    • Cheryl Greene

      Biswajit,

      Yes, it is possible for the father to have B+ blood, the mother to have O+ blood and their child to have O- blood.

      If you would like an explanation, please let me know.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  217. Misty

    My mom had O- and my dad had B+. I have A+. Is this possible? My younger sister was born Rh- and got a complete blood transfusion. No other siblings. I look like my mom.

    Added:
    • Cheryl Greene

      Misty,

      If your mother is O- and you are A+, your father is A+ or AB+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  218. Liss

    I am ab-. my mom is ab+ and her sister (my aunt) is o-. Can this be possible having the same parents?

    Added:
    • Cheryl Greene

      Hi Liss,

      If your grandparents were type A and type B and at least one of them was Rh+, they could have children who are AB+ and O-. There are no other combinations that would work, but that’s a fairly common combination (though I can’t tell you how common — sorry).

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  219. Sherry

    Hi I’m O+ with a D factor I don’t know what that means my mom is AB/RH- my dad is A +
    When I was told as a child I was A+ with the D Factor but @ 18 I found out I was O+ with the D Factor.
    is it possible for me to Be this with my parents having these blood type?

    Added:
  220. Michelle

    I am RH B- and my daughter is A- and her father is O+. Is that possible

    Added:
    • Cheryl Greene

      Michelle,

      If the mother is B- and the child is A-, the father must be AB+, AB-, A+ or A-. He can not be O+, O-, B+ or B-.

      Blood types are often different than thought. The next step would be to re-test all three blood types.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  221. Linda

    Can A+ mom and O- father have O+ child?

    Added:
    • Cheryl Greene

      Hi Linda,

      Yes, an A+ mother and an O- father can have an O+ child.

      If you’d like an explanation, please let me know.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  222. Aimee

    Hello,
    I haven’t had a chance to scan through all these yet to see if this question has already come up but I just realized that my mother is O Rh- and I am AB Rh-. (My father can’t recall what type he is.)

    Could you explain this scenario a bit. This seems a bit unusual?

    Many thanks,
    Regards,
    Aimee

    Added:
    • Aimee

      Oh, I should maybe add that my mother has previously had O- transfusion without incident.

      Added:
    • Cheryl Greene

      Aimee,

      I can not explain this. If you are AB- you had to get an A from one parent and B from the other and an Rh- from each of them.

      Perhaps it’s time for everyone to be retested?

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  223. Christina

    If mother is rh- negative and baby is Rh-positive , what is Father?

    Added:
  224. Vanessa Martins

    Hi, my husband and I are both O+ but our daughter has A- blood. My mother has A- blood also. I don’t need to do a paternity test because my daughter looks EXACTLY like my husband. Is it possible she has A- from my mother? It’s a little concerning to us.

    Added:
    • Cheryl Greene

      Vanessa,

      This is not a combination that is considered possible. The most likely explanation is one of the blood types is different than you think it is. You may want to have all your blood retested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
    • Mel

      I’m not a doctor but I’m on the same boat. Both my parents are both O+ and all my siblings are all O blood type. However on the other hand, I’m the odd daughter with the B+ blood type. All my family donated blood several times, so obviously they can’t be retested or questioned for their blood type. But as for me, I’ve gotten my blood tested several times lately and sure enough I’m still B+. For some reason I thought I read somewhere that it is possible that a baby can inherit their parents’ parents or from an uncle or aunt. I have no doubt that my dad is my dad. I look exactly my dad from skin, hair, feature and personality. I think it is possible to inherit any of the parents’ closed blood type relative.

      Added:
  225. James

    Me and my wife just welcomed our new baby boy to the world. We are both O positive and the baby is B negative. We are confused on how it is possible. Any help would be appreciated.

    Added:
    • Cheryl Greene

      Hi James,

      Congratulations!

      In a case like yours, it’s often wise to have all blood types retested. As you’ve already figured out, that’s not an outcome that is considered possible.

      If you are still concerned after retesting all three of your blood types, a DNA paternity test is the only test considered definitive. They are fairly inexpensive, can be ordered online, taken in the privacy of your own home, mailed in, and results received by mail. They are considered 99.999% accurate. Here is an example of one such test.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Sarika

        Hey…..I am A+my husband is B+my daughter is ab-and my son o+ what do u think about this scenario ? How rare is it?

        Added:
        • Cheryl Greene

          Sarika,

          If you are A+ and the father of your children is B+, there is a 56.25% chance each child will be AB and a 6.25% each child will have type O blood. There is a 93.75% chance each child will be Rh+ and a 6.25% chance that each child will be Rh-. It’s all very interesting, right?

          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          Added:
  226. Tina

    If child is Rh- is it possible to have parents that are(father) b and (Mother)a?

    Added:
    • Cheryl Greene

      Tina,

      It is possible for a child to be Rh- if his or her parents have type B and type A blood.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Tina

        My baby is Rh O+ does that mean she has rh factor?

        Added:
  227. Husna

    If my father is A+ and mother is B+, what am I?

    Added:
    • Cheryl Greene

      Husna,

      If your father is A+ and if your mother is B+, you could be AB+, AB-, A+, A-, B+, B-, O+ or O-. As you’ve probably figured out, this combination of parents is the only combination that doesn’t rule out any possible blood type in the child.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  228. courtney

    I am o positive. The father of my child is b negative. My son is a positive. Is that possible?

    Added:
    • Cheryl Greene

      Courtney,

      If one parent is Rh+ and the other is Rh-, each of their children can be Rh+ or Rh-.

      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  229. Joyce

    My mom told me when I was younger I was a+. So I told the doctors I’m a+ even the obgyn.. I didn’t find out till my 4th child I was o+.. my half siblings and my full blood brother r a+ like my dad and my mom is a- is there a possibility that my dad is my dad I don’t look anything like him but my sister and brothers do.. and my mom side of the family told me when I was 28 that my dad isn’t my dad.. and that I look like the other guy my mom was with when she was 16

    Added:
    • Cheryl Greene

      Joyce,

      If your mother is A+ and if your father is A+ you could be A+, A-, O+ or O-.

      Only a DNA paternity test can actually tell you if the man who raised you is your biological father, but these blood types don’t bring his paternity into question.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  230. Ann

    my father is a B and my mother is a RH and I am an O how does that make any sense

    Added:
    • Cheryl Greene

      Ann,

      Blood types are comprised of two alleles. The most common (by far) are A, B, and O. We call blood types A, B, O and AB. but people with type A and B can also have an O allele. Here’s how that looks:

      1) If a person has type B blood he or she could have two B alleles (BB) or one B and one O allele (AO).
      2) If a person has type A blood, he or she could have two A alleles (AA) or one A and one O allele (AO).
      3) If a person has type O blood, he or she has two O alleles (OO).

      In the scenario you suggested, you could have received an O from each parent and you would then be type O.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  231. Lyn

    If im a B+, my husband is AB, wht will be my child blood type?

    Added:
    • Cheryl Greene

      Lyn,

      If you’re B+ and the father is AB, your child could be AB+, AB-, B+ or B-, but not A+, A-, O+ or O-.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Co-founder & Executive Producer, DrGreene.com
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  232. Ellen

    To have a child that is RH-, what type does the parents have to be.

    Added:
    • Cheryl Greene

      Ellen,

      If a child is Rh-, the parents can be either Rh- or Rh+.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  233. Amanda

    If my mother is O+ and my father is AB+ what is my blood type?

    Added:
    • Cheryl Greene

      Hi Amanda,

      If your mother is O+ and your father is AB+, you could be A+, A-, B+ or B-.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  234. Sarah

    If I am rh- and my child is rh- what must my ex husband be

    Added:
    • Cheryl Greene

      Sarah,

      He can be Rh- or Rh+.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  235. Hazel

    If my mother was AB- and I am B+, what should my father be?

    Added:
    • Cheryl Greene

      Hazel,

      If your mother was AB- and you are B+, your father could be B+, AB+ or O+.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am not Dr. Greene, nor am I a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Hazel

        Thank you.

        Thank you … what about an AB- mother with an A- child. What could the father be there?

        Added:
        • Cheryl Greene

          Hazel,

          If the mother is AB- and the child is A-, the father could be A+, A-, B+, B-, O+, O-, AB+ or AB-.

          Let me know if you’d like an explanation.

          Best, @MsGreene
          Co-founder & Executive Producer DrGreene.com, Mom
          Note: I answer a lot of questions on DrGreene.com, but I am not a doctor.

          Added:
  236. Rana singh

    Hi… My brother have A+ and his wife AB+ but their son is O+ how is it possible??? Please reply me

    Added:
    • Cheryl Greene

      Hi Rana,

      Typically we say that this is not possible — an AB mother can not have an AB child — however there is a very rare blood type (0.0004% or about 4 per million in the general population) known as the Bombay Blood type. In some places such as Mumbai (which was formerly called Bombay) the occurrences can be as high as 0.01% or 1 in 10,000. This group does not fall into the ABO system and the usual tests for ABO blood show them as group O.

      The Bombay blood type is usually only found in small communities where there are other people with the hh blood type. Both parents have to be h carriers, though a parent can be a carrier without actually having Bombay type blood.

      If you suspect a child may have the Bombay blood type talk to the child’s doctor about a specialized test for this blood type as it does not show up using the normal ABO blood type tests.

      DNA paternity tests are still accurate (99.999%) with type hh blood and are considered the only accurate test for paternity.

      Best,
      @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am not Dr. Greene, nor am I a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  237. Rebecca

    Is it possible for 0+ and 0- to have a a+ baby

    Added:
    • Cheryl Greene

      Rebecca,

      Our current understanding of genetics is that it is not possible for one parent to be O-, the other parent to be O+ and their child to be A+. Two type O parents can only have a child who is type O.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
  238. JOSEPH

    Hello my wife is B- and my son is O-, what could I be thank you Dr greene

    Added:
    • Cheryl Greene

      Joseph,

      If the mother of your child is B- and your son is O-, you could be A+, A-, B+, B-, O+ or O-. You could not be Ab+ or AB-.

      Let me know if you’d like further explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  239. Ann

    Hi dr green I’m Ann I was wondering about 2 years go when I was pregnant I had a blood type test taken it came back that I was B positive and my mum told the dr that she and my dad are both are O positve how can that be the dr just looked at me as if there might be a another reason to why. The hospital did my blood type again and it came back B positive again is this possible even though when I was born they crossed matched my mum blood to Mach me for a blood transfusion as a breammacher baby by 4 months early please email me thank you Ann

    Added:
    • Cheryl Greene

      Ann,

      Have both your mom and dad’s blood been retested? It’s not uncommon for blood types to be different than they are thought.

      Our current understanding of genetics is that it is not possible for two parents with O+ blood to have a child that is B+. Two O+ parents can only have children who are O+ or O-.

      The only test to determine paternity is a DNA test. Here is a link to one example of a DNA paternity test. They are 99.999% accurate and you can take them in the privacy of your own home. The results are mailed back fairly quickly.

      I hope that’s helpful,

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am not Dr. Greene, nor am I a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Ann

        Hi degreen no my mum and dad have been retested my mum is differently o positive and my dad side he’s very sure is o positive should we do a DNA test . Thanking you Ann

        Added:
        • Cheryl Greene

          Ann,

          A DNA test is 99.999$ accurate in determining paternity. It sounds like that’s your next move.

          Best, @MsGreene
          Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

          Added:
      • Ann

        Thank so much I think we will deffirntly give that go

        Added:
  240. Mandy

    Thank you so much for an explanation that I could actually understand!!

    My husband is type AB- I am O- and our son is A+

    Our doctor insisted that he could not be ours and forced a DNA test on all 3 of us to prove he was ours. It was a hugely traumatic time and we weren’t allowed to see him or take him home until this had been performed. (Especially because just hours before this doctor saw my son come out of my body!!)

    My husband and I tried researching but it got to a point where all I understood were the “the’s and the and’s” so we didn’t get very far. I’m so glad to have come across this today!!

    Added:
  241. PAUL

    Hello DrGreene,
    is it possible for a father of A+ and a mother of B+ to give birth to a child of O+ ?

    Thanks for your anticipated response

    Paul

    Added:
    • Cheryl Greene

      Paul,

      Yes, it is possible for one parent to have type A+ blood, the other parent to have type B+ blood and their child to have type O+ blood.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
  242. L

    Thanks for this explanation. I have always wondered if my dad was my real dad, since he and my mom has O positive blood type and I am O negative.

    Added:
  243. Lala

    Hi,my blood groub o my husband b and my son b but another male in my life o who is the father to my son and can amutation change ablood groub from parents to child

    Added:
    • Cheryl Greene

      Lala,

      One type O parent and one type B parent, can have a child that is type B. Two type O parents can not have a child that is type B.

      Mutations are extremely rare.

      The only accepted test for paternity is a DNA test such as this one.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  244. Cuddles

    I was told by mistake that my dad wasn’t my dad when I was 15 by my sister then she said it cause she was angry,I recently gave blood and found out I’m a b positive ,my dad has passed away but does that mean that one of my parents have to be a b.

    Added:
    • Cheryl Greene

      Cuddles,

      I’m so sorry for your loss and even sorrier that this is now coming up as an issue for you.

      If you are B+ one of your parents is B+, B-, AB+ or AB-. Bottom line, the B has to come from one of your parents.

      I hope that helps,

      @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am not Dr. Greene, nor am I a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  245. Erica

    Could be possible im o+ and my hubby is a could be possible if my daughter is b+?

    Added:
    • Cheryl Greene

      Erica,

      Our current understanding of science is that it is not possible for one parent to have type O blood, the other parent to have type A blood and have a child that has type B blood.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are are thought to be.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
  246. Harold

    Two strange situations here. My wife’s father was AB+ and her mother was O+. My wife’s blood type is O+. Genetic testing shows that both her parents are her biological parents. We didn’t think this was possible, yet it is. Second situation. I am O+ and my wife is O+. We have three sons. The oldest is O-. The second son tested O+ at birth. The third son is O-. When my second son’s blood was retested a couple of days ago, he tested O-. Is this possible? Could you explain these two situations to me? Thanks for the help.

    Added:
  247. Diianna Harrold

    Can an a negative father and a o positve mother have a o positive child

    Added:
    • Cheryl Greene

      Dilanna,

      Yes, if the father is negative and the mother is positive, they can have a child who is positive. Actually, it doesn’t matter which parent is positive or negative. If one parent is positive and the other is negative, they can have either a positive or a negative child.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  248. Abbey

    Can a mother with a+ and a father with ab+ make a b- baby ??

    Added:
    • Cheryl Greene

      Hi Abbey,

      Yes, a mother with A+ blood and a father with AB+ can have a child with B- blood.

      Hope that helps,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
  249. Samantha Collins

    My sister is O+ve and I am AB-ve is this possible for full siblings?

    Added:
    • Cheryl Greene

      Samantha,

      Yes, if one parent is A+ or A- and the other is B+ or B-, they can on child who is AB- and one child who is O+.

      If you’d like an explanation, please let me know.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
  250. Kim

    My mother is A- my father is A+ I’m O+ is the possible?

    Added:
    • Cheryl Greene

      Hi Kim,

      Yes, this is possible and even common.

      Let me know if you’d like further explanation.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
  251. Tammy

    Hello I was wondering if my father is A positive and my mother is ab positive is it possible to have a ab negative baby

    Added:
    • Cheryl Greene

      Tammy,

      Yes, it is possible for an A+ parent and an AB+ parent to have an AB- child.

      Let me know if you’d like an explanation of how this can happen.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      • Tammy

        Thank you so much… you have answered all my questions…

        Added:
        • Cheryl Greene

          You are most welcome!

          @MsGreene
          Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

          Added:
  252. James

    Is it possible if wife blood type is O
    husband believe he has blood type is O – since both his parent bloody type is O
    daughter have blood B+ is that possible?

    Added:
    • Cheryl Greene

      James,

      Our current understanding of genetics is that it is not possible for two type O parents to have a child that is type B. Two type O parents can only have type O children.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are thought to be.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      • James

        Thanks so much @MsGreene
        really appreciate for writing back to me.

        Added:
  253. Shruthi

    Hello,

    My father is A+ve and we our siblings have below blood groups;
    1st child A+ve
    2nd Child O-ve
    3rd child A-ve
    4th Chile A+ve

    Is it possible to have these, also could you please let me know what would be my mother’s blood group.

    Added:
    • Cheryl Greene

      Hello Shruthi,

      Yes, this is a possible outcome. If one parent is A+ and the other is either A+, A-, B+, B-, O+ or O-. The only group the other parent could not be is AB+ or AB-.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  254. Ashley

    If I am o negative and my baby is o negative what is my husbands blood type?

    Added:
    • Cheryl Greene

      Hi Ashley,

      If you are O- and your baby is O-, the baby’s father could be O+, O-, A+, A-, B+ or B-. He could not be AB+ or AB-.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
  255. Toni

    My family did a home blood test, eldon card kit. I am AB+, my husband is O+, our eldest daughter is A+ and our youngest daughters test said O+. We retested her because I read that AB+ and O+ parents cannot have an O+ child. After retesting we got the same results. No agglutination is anti-A or anti-B. Another O+. Is that even possible? At all? Even a small chance? I will say she is a very unique child haha- but she is definitely the product of my husband and I. I know my husband and my own blood types are correct, this was just for the kids and for a little science experiment.

    Added:
    • Cheryl Greene

      Toni,

      You are correct, an AB+ parent can not have a child who is O+. You may want to retest your blood types with a clinical lab.

      If the results are the same, you might consider a DNA paternity test, though in this case it would be a maternity test. You can buy the kits online. Here’s one example. They are 99.999% effective.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Smith

        This is disgraceful if you really knew what you were talking about you would have heard of the Bombay blood group where AB parents can have what appear to be O children. It is rare but coming from a family with Bombay blood I happen to know about it. My question to you is: why don’t you rather than frightening people into thinking that they are not true offspring?

        Added:
        • Cheryl Greene

          Smith,

          Thanks for your comment. I love to learn and will delve into the Bombay blood group research. My current understanding it that it is extremely rare and DNA tests (which I strongly suggest to people who have questionable combinations) are still 99.999% accurate.

          Best,
          @MsGreene
          Co-founder & Executive Producer DrGreene.com, Mom
          Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

          Added:
          • Cheryl Greene

            Hi Smith,

            I’ve done some research and think I have a better handle on this. I tried to email you to discuss, but the email address you provided bounced. If you’d like to discuss more, please reach out again.

            Best,
            @MsGreene
            Co-founder & Executive Producer DrGreene.com, Mom
            Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

            Added:
    • Cheryl Greene

      Toni,

      There is a possible explanation after all (thanks Smith for pointing this out in your comment below).

      There is a very rare blood type (0.0004% or about 4 per million in the general population) known as the Bombay Blood type. In some places such as Mumbai (which was formerly called Bombay) the occurrences can be as high as 0.01% or 1 in 10,000. This group does not fall into the ABO system and the usual tests for ABO blood show them as group O.

      The Bombay blood type is usually only found in small communities where there are other people with the hh blood type. Both parents have to be h carriers, though a parent can be a carrier without actually having Bombay type blood.

      If you suspect your child may have the Bombay blood type talk to your doctor about a specialized test for this blood type as it does not show up using the normal ABO blood type tests.

      DNA paternity tests are still accurate (99.999%) with type hh blood and are considered the only accurate test for paternity.

      Best,
      @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am not Dr. Greene, nor am I a doctor. Please keep that in mind when reading my comments and replies.

      Added:
  256. lisa

    My mother is o+ and im b+ what would my fathers bloof type be?

    Added:
    • Cheryl Greene

      Lisa,

      If your mother is O+ and your father is B+, you could be O+, O-, B+ or B-.

      If you’d like an explanation, please let me know.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
  257. Mariam

    My blood type is A,my daughter’s blood type is N, what should her father’s blood type be?

    Added:
  258. Michelle

    Hi,
    My mother is type A positive and I am type A RH negative. What would my father need to be?
    Thank You

    Added:
    • Cheryl Greene

      Hi Michelle,

      If your mother is A+ and you are A-, your father could be A+, A-, B+, B-, O+, O-, AB+ or AB+. Basically, no blood types are eliminated with this combination.

      If you’d like an explanation, let me know.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  259. christal

    I need to knoe if two parents are o postive and already have a child 0 postive and have a second child but that baby is a pos is that a possibility

    Added:
    • Cheryl Greene

      Christal,

      Our current understanding of science is that it is not possible two parents who are O+ to have a child that is A+. If one parent is O+ and the other is A+ or A-, it would be possible for them to have one child who is A+ and another child who is A+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
      • Chinna

        Is it possible both parents blood group is O positive and child is A positive blood group ?

        Added:
        • Cheryl Greene

          Chinna,

          If a child is A+, both of her parents can not be O+.

          It is not uncommon for one of the blood types to be different than thought, so it is wise to have all three types retested.

          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          Added:
  260. Viky

    Hi doc. My mother blood group is O+ and my father B+. And my blood group is O-. Is it possible?😐

    Added:
    • Cheryl Greene

      Hi Viky,

      Yes, it is possible for one parent to be O+, the other parent to be B+ and the child to be O-.

      If you’d like an explanation, let me know.

      Best, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  261. Unknown

    Can an A+ and O make a child of A+

    Added:
    • Cheryl Greene

      Unknown,

      Yes, this is a possible outcome.

      If you’d like an explanation, please let me know.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  262. Unknown

    Hi, my blood type is the same as my mom but not my dad. My second oldest sister is the same as my dad. To me I have no father at all. I really don’t see features of me in him at all, but force myself to believe. My mom I feel has been hiding so much since I was a little girl. I have traumatic brain injury since 2013 from assault by her boyfriend. But, I still don’t see me in my dad. I found my dad in 2006. I have no recollection of him at all. My mom and him try to force memories on me that I don’t know. I didn’t see my dad from age two or three until I was almost 29.

    Added:
    • Cheryl Greene

      Unknown,

      If you want to have a real confirmation that he is your father, a DNA paternity test is in order. They are 99.999% accurate. Here is one example of a DNA paternity test you can buy online. The two of you can take the test at home and mail it in, so you don’t even need to go to a lab.

      I hope this helps, @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  263. Trisha

    i’m at a lost. My whole life, since I can remember, my siblings would joke I was adopted. I gave blood at 17 years old and found out I’m O+. My dad is AB+ and my mom is A+. My sisters are A+. Please help me figure out how that is possible? I’d ask them but I’m too scared to.

    Added:
    • Cheryl Greene

      Trisha,

      Our current understanding of genetics is that it is not possible for one parent to be AB+, the other parent A+ and a child that is O+. An AB parent can only have children who are A, B or AB. An AB+ parent and an A+ parent can have children who are A+, A- B+, B-, AB+ or AB-.

      I know this would require discussing it with your parents, but it is wise ask them. If they say you are their biological child, ask to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  264. Susie Gresham

    Hi, not sure if my question posted or not. Can a O positive person and a Rh negative person have a A positive baby?

    Added:
    • Susie Gresham

      So are you saying yes or no?

      Added:
      • Cheryl Greene

        Susie,

        I’m sorry. There was a very confusing error in my last answer to you. I’ve edited it, but here it is (to make it easier for you to find what is changed):

        Blood types have two identifiers. The first is A, B, O or AB. The second is Rh+ or Rh-, which we simply call + or – after the letter. As an example, O+.

        You don’t seem to know if the person you list as “Rh-” is A-, B-, O- or AB-. If that parent is A- or AB- then the answer is yes, it is possible. But if the second parent is O-, or B- the answer is, no.

        Best, @MsGreene
        Co-founder & Executive Producer DrGreene.com, Mom
        Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

        Added:
  265. Sanjhna

    My blood group is B-ve and my husband’s blood group is O+ve. My newborn baby is having B+ ve. I am confuse Is that possible. Lab technician said its rare??

    Added:
    • Lalita

      Hello Dr. Greene,

      My sister recently gave birth to a baby boy. She is bit confuse about her babies blood group who is B+ve. she is B-ve and her husband is O+ve. Is that possible??

      Added:
      • Cheryl Greene

        Lalita,

        Yes, that is completely normal. If you’d like an explanation, let me know.

        Best, @MsGreene
        Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

        Added:
    • Cheryl Greene

      Sanjhna,

      Yes, it is possible for one parent to be B- the other to be O+ and the baby to be B+. There is nothing to worry about.

      By rare, she just means it is not as common as O+ blood types. This doesn’t not mean your child has any additional risk of health issues based on blood type. The only time this would be an issue is if your baby needs a blood transfusion as this blood type is not as common as others, it might be harder to find.

      Best,
      @MsGreene

      Added:
  266. Robin

    My parents, grandparents, and 2 brothers are o positive. I am b negative. How is this possible?

    Added:
    • Cheryl Greene

      Robin,

      Our current understanding of genetics is it is not possible for two O+ parents to have a child that is B-.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  267. deb kelly

    Can a a- and a+ have a b-

    Added:
    • Cheryl Greene

      Deb,

      Our current understanding of science is that it is not possible for one parent to be A-, the other parent A+ and their child to be B-.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  268. Lakshmi

    My blood group is b+be,my husband blood group is ab-be and daughter blood group is ab+be is it possible.

    Added:
    • Cheryl Greene

      Lakshmi,

      Yes, that is a possible outcome.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  269. Rhonald Mitchell

    My dad is O and my mum is RH negative why am I AB positive

    Added:
    • Cheryl Greene

      Rhonald,

      Our current understanding of science is that it is not possible for one parent to have type O blood and have a child that is type AB. An AB parent can only have children who are A, B or AB.

      It is wise to have both your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  270. Rachel

    Hi there, is it possible for siblings to each have completely different blood types, I am B Rh(D) positive, my older brother is B negative and my younger brother is O positive. We think our Dad is bloody type O. My older brother had blood transfusion as a baby, does this effect it?

    Added:
    • Cheryl Greene

      Rachel,

      If one parent has type O blood and his or her children are B+, B- and O+, the other parent would be type B (likely B+, but could be B- if the first parent is O+).

      I hope that’s helpful, @MsGreene
      Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  271. Korine

    Hi,

    My husband is has the blood type A+ and I have B+. We had a baby that was tested AB+ when he was born and four years later B+. Is it normal for a blood type to change?

    Thank you

    Added:
    • Cheryl Greene

      Korine,

      It is not normal for a blood type to change, but it is not at all unusual for blood type tests to be inaccurate.

      Best,
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
  272. Korine

    Hi,

    My husband have the blood type A+ and and I have B+. We had a baby boy who is A -. The Rhesus – could be a problem for him?

    Thank you

    Added:
    • Cheryl Greene

      Korine,

      It is possible for two parents with Rh+ blood to have a child that is Rh-. This should not cause a problem for the child.

      Best,
      Co-founder & Executive Producer DrGreene.com, Mom
      Note: Not Dr. Greene, not a doctor. Keep that in mind when reading my comments and replies.

      Added:
  273. Jorge Leon

    Hello

    Mother is O positive and father is AB positive . Baby is A positive with anti RhD positive antibodies
    Is this possible ?

    Thanks !

    George

    Added:
    • Cheryl Greene

      Jorge,

      Yes, this is a possible scenario. Baby got an A from dad and an O from mom, making baby A.

      Let me know if you’d like an explanation.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
  274. Ruby G

    Hi my Name is Ruby

    My blood type is B-
    But my parents blood types are Mother B+ and Dad O+
    is this possible ?

    Added:
    • Cheryl Greene

      Ruby,

      Yes it is possible for a child to be B- if his or her parents are B+ and O+.

      If you’d like an explanation, please let me know.

      Best, @MsGreene
      Note: I reply to a lot of the comments on DrGreene.com, I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  275. Charlie McAdams

    I’m a+ my husband is a something and our daughter is 0- possible???

    Added:
    • Cheryl Greene

      Charlie,

      Yes, it is possible for an A+ mother to have an O- child.

      Let me know if you’d like an explanation.

      Best, @MsGreene
      Note: I reply to a lot of the comments on DrGreene.com, I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  276. edilyn

    hello :) my mother is blood type A and my father is blood type O and me is blood type b+ it could be their my real parents ?

    Added:
    • Cheryl Greene

      Edilyn,

      Our current understanding of science is that it is not possible for one parent to be A, the other parent O and a child that is B.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      Best, @MsGreene
      Note: I reply to a lot of the comments on DrGreene.com, I am the co-founder of DrGreene.com and Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

      Added:
  277. Flora

    Hello :) if i am is blood type 0 then my son is blood type b? What could be my husband’s bloodtype? Thanks

    Added:
    • Cheryl Greene

      Flora,

      If your blood type is O and your son’s blood type is B, the father must be B.

      People with type O blood, unlike A and B, can only pass down an O allele. As can pass down an A or an O. Bs can pass down a B or an O. ABs can pass down an A or a B.

      Best,
      @MsGreene

      Added:
  278. liz

    Hi dr. I just recently gave birth. My husband and I are both A+. But now my 2nd baby who exactly looks like my 1st born have O+??? How is it even possible? I checked with the hospital and said it is the correct blood type? Pls advise. Thanks

    Added:
    • Cheryl Greene

      Liz,

      Blood types are determined by two alleles. People who have type A blood can either have two A alleles (AA) or one A and one O (AO). Both are called type A. It sounds like in your situation, both parents are AO and each one passed down the O allele, so the baby is O.

      Does that make sense?

      @MsGreene

      Added:
      • liz

        Yes, now that u said it. Thanks a lot :)

        Added:
  279. Angela Giles

    Mother’s bg =A negative and
    Fathers bg=A+.
    2x siblings have A+ and 1x sibling has AB + .Is this possible

    Added:
    • Cheryl Greene

      Angela,

      Our current understanding of science is that it is not possible for two parents with type A blood to have a child that is type AB.

      It is wise to have both parents and the child you think is AB retested. It’s not uncommon for blood types to be different than they are remembered and if one of the parents was type B instead of type A, all this would be perfectly normal.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
  280. sonia

    hi i m sonia… plz tell me if father blood group is B+ n mother blood group is A+ den child can be o negitive?

    Added:
    • Cheryl Greene

      Sonia,

      Yes, if one parent is B+ and the other is A+, it is perfectly normal for their child to be O-.

      If you’d like an explanation, please let me know.

      Best,
      @MsGreene

      Added:
  281. sandy

    I have the same question about my parents if neither have rh- blood. my dad had o+ and I think my mother had the same. I didn’t know I had rh A – until I was pregnant with my second child. I then had to take a shot to lessen another baby having my blood type after my son was born. Both kids did not have my blood type. I had two more kids with no problems. I wasn’t told until way later own I shouldn’t have more children because of my blood type. I always had the question of how I got my type blood. I am the middle daughter of six brothers and no sisters. None of my brothers have my blood type. I spent a lot of years wondering how I got it. and felt I didn’t belong. I guess I want just plain English that I belong to my parents. All this plus and minus blood types are confusing.

    Added:
  282. Stefanie lee

    Hello i need to asks why my Bro and I have share same blood group type of B positive while my mom is A positive and my dad is O positive?

    Added:
    • Cheryl Greene

      Stefanie,

      Our current understanding of science is that it is not possible for one parent to be A+, the other parent O+ and a child that is B+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
      • Andrew Khoury

        It is possible under one condition, which is mutation by recombination. This was published in a study by Stanford University by Nathalie Dye. Mutations are very likely to occur. I’ve had extensive research on this topic where such blood types occurred and with specific laboratory testing, proving that it is possible when DNA tests showed both parents to have an offspring of a different blood type.

        Added:
      • Stefanie Lee

        Just found out I’m not theirs biological….25 years!!!!they have been kept it secret for 25years….I dont feel so great…..wonder where is my biological parent are and how does they looks like…..should I searched for them…..or just stay as usual pretend nothing happens?

        Added:
        • Cheryl Greene

          Stefanie,

          It sounds like this has hit you very hard. The decision to search for one’s biological parents is a personal one. It helps some people, but not everyone.

          It is often helpful for adopted children to discuss the situation with this adopted parents and try to understand their perspective. In the process, it may be very helpful to talk with a counselor to help work through the feelings associated with this kind of revelation.

          Sincerely, @MsGreeene
          Co-founder & Eecutive Producer, DrGreene.com
          Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner and wife, but I am a not doctor. Please keep that in mind when reading my comments and replies.

          Added:
          • Stefanie Lee

            Guess will try to talk to someone before searching for the biological parents. I just need some time to digest the fact I’m their adopted daughter.

            Added:
  283. Adonis

    Is it possible to have a B blood type if my parents have O and O…?

    Added:
    • Cheryl Greene

      Adonis,

      Our current understanding of science is that it is not possible for both parents to have type O blood and their child to have type B blood. Two type O parents can only have a type O child.

      It is wise to have all your blood retested. If one of your parents was type B or AB, then you could be type B. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
  284. Salma Ahmad

    Hi Dr greene my name is salma
    my father BG is A+ my mother BG is A+ .we are 4 siblings my 3 siblings have BG A+ while i m having BG B+ ..is it Possible that a child could have such blood group while both mother and father A+ blood group??
    or there may be some mistake in my blood group report ?

    Added:
    • Cheryl Greene

      Hi Salma,

      Our current understanding of science is that it is not possible for two parents with A+ blood group to have a child that is B+.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
  285. Danni

    My mothers bloodtype was a-, fathers bloodtype is b+ my bloodtype is O+ does this make sense? Only recently we found out that one father was not the same as another sibling who had a- mother a- her father a+ bloodtypes…maybe I’m just being paranoid but that was over thirty years of a lie. I just want to know if mine makes sense?

    Added:
    • Cheryl Greene

      Danni,

      If your mother’s blood type was a-, your father’s blood type is b+, it is possible for your blood type to be O+.

      If you’d like an explanation, let me know.

      @MsGreene

      Added:
  286. Mary

    Hello, my mother was O+ and her husband was AB-. I have six sibling: their blood types: brother AB- , brother AB-, brother B-, sister O- , brother B+, brother O- and I have O+ . My mother told me before she died that my father was her landlord’s 19 year old son. Could AB- and an O+ have an O+ child?
    Thank you for any help.

    Added:
    • Cheryl Greene

      Mary,

      Our current understanding of science is that it is not possible for one parent to be AB-, the other parent O+, and have a child that is O+. An AB+ parent and an O+ parent can only have children who are A+, A-, B+ or B-.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
  287. Emma Ibbitson.

    Hello Dr Greene,

    I have spent countless hours searching for an answer to me shall I call it, predicament. See I am a B Rhesus Neg. My Mum was a O+ and my dad was I believe a A+. This is where it gets confusing for me. I have four other siblings, none of them share the same blood group as me. I have asked my Mum (before she passed awäy 2 years ago) why my blood is different to my siblings and she couldn’t answer. I cannot ask my Father as he passed away when I was very young. Could it be a genetic mutation or like people keep telling me, I may have a different Father. I know my BG is correct as I’ve had all the D injections etc. Now I have no one left to ask, I feel lost.

    Added:
    • Cheryl Greene

      Emma,

      I’m so sorry you have no one left to ask. Often in these situations, someone’s blood type is different that thought. For instance, if your father was B+ or B-, and your mother was O+, you could be B-.

      Best,
      @MsGreene

      Added:
  288. Ella

    My mother is O+ and my father is B+, and I am B-, is he my father that gave birth to me.?

    Added:
    • Cheryl Greene

      Hi Ella,

      If your mother has O+ blood and you have B- blood, it is possible that your birth father has B+ blood.

      Some times, blood types can rule out a potential father, but they can not determine paternity. The only way to determine if he is your birth father is to take a DNA paternity test. They are 99.999% accurate.

      Good luck on your search,
      @MsGreene

      Added:
  289. Christy

    Hello dr. My blood type is o neg my husband is o pos and my oldest and youngest daughter are o pos. Me and my husband weren’t together when i got pregnant with my youngest the other male is bpos could the other male be my daughters father or my husband?

    Added:
    • Cheryl Greene

      Christy,

      These blood types don’t exclude either possible father. If you really want to know, DNA paternity testing is 99.999% accurate.

      Best,
      @MsGreene

      Added:
  290. Elaine Reiser

    Hi Dr. Greene. There has always been a question of my paternity and today I finally got the answer that I needed. My father is B+ and my mother is B+, I am AB+. I conclude that my “father” is really not my biological father. Is that what you would suppose also?
    Thanks,
    Elaine

    Added:
    • Cheryl Greene

      Elaine,

      First, blood types are often different that what they are thought to be. Possibly an error in the test or in the recording. But, our current understanding of science is that it is not possible for two B+ parents to have an AB+ child.

      I hope this is helpful,
      @MsGreene

      Added:
  291. Jb

    Hi dr. Greene,

    My name is jb frm phillipines, i want to know that is there a
    Possible that my family have 3 blood type. My father is O+, my mothere is A+. We are 5 their children, we r 4 girls n 1 elder brother.
    3 of my sister are blood type is A+, my brother is AB+, then my blood type is B+. Can u xplain this to me, kindly plss i need the explanation about this plss help me. Thank u very much if u give me short time for this Godbless

    Added:
    • Cheryl Greene

      JB,

      For a child to be AB the parents must be A and B, or AB and A, or AB and B. According to our current understanding of genetics, an O parent can not have an AB child. Also an O parent and an A parent can not have a B child.

      Before you jump to any conclusions, it’s wise to have everyone’s blood retested. For more accuracy, you can do DNA paternity tests that are 99.999% accurate.

      Best,
      @MsGreene

      Added:
  292. Kate

    Hello, my father was AB neg and my mother was O pos. My two sisters are A neg and B neg respectively. I am rhesus neg O is that possible?. Really need to know thanks.

    Added:
    • Cheryl Greene

      Kate,

      Our current understanding of science is that it is not possible for one parent to be AB-, the other parent O+ and a child that is O-. An AB parent can only have children who are A, B or AB.

      It is wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
  293. Steph

    My mother is B+ and my father is O+ . I am AB+ can my father be my father?

    Added:
    • Cheryl Greene

      Steph,

      Our current understanding of science is that it is not possible for one parent to be B+, the other parent O+ and a child that is AB+. The only blood types a child can have if the parents are B+ and O+ are O+, O-, B+,or B-.

      It would be wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
  294. Lyn cook

    I have two daughters with rhesus neg blood type does this mean my other three will have the same,one daughter is in a turmoil that her dad isn’t her dad after all?

    Added:
    • Cheryl Greene

      Lyn,

      No you can not assume that if two siblings are Rh-, the other three are Rh-, unless you know both parents are Rh-.

      If one parent is Rh+ and the other is Rh+ or Rh-, they can have children that are either Rh- or Rh+.

      The best way to determine paternity is a DNA paternity test. You can purchase these online and collect DNA samples at home, then send the tests away to a lab. They are 99.999% accurate.

      Best,
      @MsGreene

      Added:
      • Lyn cook

        Thankyou for that reply. I am o+ not sure of my husband. So my kids could be different blood types?

        Added:
        • Cheryl Greene

          Lyn,

          Blood types are determined by both parents, so your kids father’s blood type is very important in determining their blood type.

          Best,
          @MsGreene

          Added:
          • Lyn cook

            I am o+my husband says he is A what would that mean for my kids would they all be R-

            Added:
          • Cheryl Greene

            Lyn,

            I don’t know what you mean by “R-“. Do you mean “Rh-“. Also, what is your Rh type? Is it + or -?

            Best, @MsGreene
            Note: I answer a lot of questions on DrGreene.com, I am the co-founder of DrGreene.com, Dr. Greene’s business partner, but I am a not doctor. Please keep that in mind when reading my comments and replies.

            Added:
          • Lyn cook

            Still waiting for a reply,,anxious!!

            Added:
          • Lyn cook

            I am 0 positive and my husband says he is A type blood?

            Added:
          • Lyn cook

            Thankyou for those answers,we are grateful and will test our blood groups again.

            Added:
  295. Misti

    Hello Dr. Greene,

    Recently my youngest daughter (19) had her blood type checked, her results came back as B+. I am O- and my husband is A+, I understand that this is not possible according to the charts but I am 100% sure that we are her parents. Furthermore, the hospital she was born in had a stay in the room policy, so when she was born she was with me at all times with the exception of about an hour when she was chocking about 10 hours after birth. What are the possibilities here? I have been reading everything I can but am coming up empty handed.

    Added:
    • Cheryl Greene

      Misti,

      The most likely possibility one of the blood types is different than you think it is. It is very wise to have all your blood retested. If they still come back as “impossible type”, have DNA tests run.

      Best,

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
  296. Saleem Sahar

    Hi dear Doctor,

    My father is O negative, my mother is B negative and my blood group is O positive.
    Could you explain that is possible or not, Please?

    Thanks in advance!

    Added:
    • Cheryl Greene

      Saleem,

      According to our current understanding of science, two Rh- parents can not have a child who is Rh+. Before you go any further, it would be wise to have everyone’s blood re-tested. If either of your parents are Rh+, you could be O+.

      Best,
      @MsGreene

      Added:
      • Ashley RT

        Hi i am A- my dad is O- and my mom is A+ what blood group should my dads parents have?

        Added:
        • Cheryl Greene

          Hi Ashley,

          If your father is O-, his parent could have been A+, A-, B+, B-, O+ or O-. Neither parent could be AB+ or AB-.

          Best,
          @MsGreene

          Added:
          • Ashley RT

            Thanks!

            Added:
          • Ashley RT

            Hi Ms Greene

            Sorry I have one more question, my grandma has A+ and my Grandpa has O+ their son (my Uncle) has O+, my mom has A+ so does that mean that my aunt has to be either O+ or A+?

            Added:
    • Cheryl Greene

      Saleem,

      Our current understanding of science is that it is not possible for one parent to be O-, the other parent B- and a child that is O+. Two Rh- parents, can not have a child who is Rh+.

      Very wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
  297. Debbie

    You have said it is not possible for an AB parent and an O parent to have an O child. I can say it is so possible, although I’m not sure how.
    My mother is AB Neg. Has been tested many times and she is. She is also surely my mother. My father is O pos. Says so on his dog tags and has been retested. My blood type is O Pos. I’ve been tested multiple times. I also have three other siblings with O pos blood. Only one has been retested.
    According to current understanding I realize this is not suppose to be possible yet here I am. I have heard of Bombay blood type but this does not apply.
    Any ideas on this?

    Added:
    • Cheryl Greene

      Debbie,

      There are very rare mutation. If this is one, you should go to a major university genetics department and tell your story. If the blood types are confirmed, they may well want to study your family.

      Best,
      @MsGreene

      Added:
      • Debbie

        Dr. Greene,
        Thanks for your reply.
        I’ve searched for years for someone to help me understand how this is possible but no one seems interested. Either that or doubt the facts, which are verifiable.
        Any suggestions on who would be interested?

        Added:
        • Cheryl Greene

          Where do you live?

          @MsGreene

          Added:
          • Debbie

            Center Kentucky/Tennessee border. Would be willing to travel if it helps advance science.
            Thanks again.

            Added:
          • Cheryl Greene

            Debbie,

            I am unfamiliar with the work of major universities in your part of the country, but there are two things I would suggest:
            1) Have all of the members of your family group take a 23andMe test or other DNA test, such as DNA Paternity Test. This will give you a DNA “fingerprint” that links you to each other. NOTE: Before you purchase any kit like the ones listed above, be sure to contact them and ask the best way to test your entire family and prove your relationship to each other.
            2) Once you have the results, contact major research university near you. Ask for the genetics department and tell them your story. There may not be anyone working on these issues in that department or even that university, but they may know of someone in a different department or different university that they can refer you to as your next step. This may take many phone calls before you find someone who is doing research in this area.

            I hope that’s helpful.

            Best,
            @MsGreene
            Co-founder and Executive Producer, DrGreene.com

            Added:
  298. Maya

    Hello Dr, my mother is A+ My father is O + . My blood type is b + and my brother is Ab + is that possible ? Please i needur help

    Added:
    • Cheryl Greene

      Dear Maya,

      The combination you describe is not possible given our current understanding of genetics, but it is not unusual for one blood type to be different than what you think it is. For instance, if the mother is A+, one child is B+ and one child is AB+, they could have the same father if he was B+ or B-.

      I hope that’s helpful.
      @MsGreene

      Added:
  299. Kathy

    My mother was o positive and my dad is AB neg can they have a child who is AB? Could my mom have an AB child with someone else?

    Added:
    • Cheryl Greene

      Kathy,

      According to our current understanding of genetics, a parent with type O blood can not have a child with AB blood, no matter what the blood type of the other parent is.

      A child with AB blood can have one parent with A and one with B, or any combination of A, B and AB, i.e. A and AB, B and AB, AB and AB.

      Before jumping to any conclusions, please consider having everyone’s blood re-tested. It is not at all uncommon for blood types to be different than they are remembered.

      I hope that’s helpful.
      @MsGreene

      Added:
  300. mumu

    Hello dr.greene
    I want to know that if blood grp is O+ and my wife’s is also O+ but my son’s blood grp is A+..is it possible??

    Added:
    • Cheryl Greene

      Mumu,

      Our current understanding of science is that it is not possible for both parents to be blood type O+ and a child that is A+ blood type.

      It would be very wise to have all your blood retested. It’s not uncommon for blood types to be different than they are remembered.

      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
  301. Ria

    Hi.
    Me and my boyfriend is both type B.. my son is type O. But my ex fiance is also type O … but i dont know thier rh.. me is B+..
    Thankss..

    Added:
    • Cheryl Greene

      Ria,

      I the mother is type B+ and her child is type O, the father could be A+, A-, B+, B-, O+, O-, but not AB+ or AB-.

      If you’d like to know why, let me know.

      Best,
      @MsGreene

      Added:
  302. Ariel bohanan

    I have rh o- blood, I’m the mom. My child has o+., what possible blood type would the fathers have? Trying to figure out something before I get a test.

    Added:
    • Cheryl Greene

      Ariel,

      If the mother is O- and the child is O+, the father could be A+, B+ or O+.

      Also, were you treated for Rh Incompatibility? If not, discuss this with your doctor before getting pregnant again.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
  303. Jitendra

    My &my wife blood group are b+ my son also b+ but my daughter o+ its possible

    Added:
    • Cheryl Greene

      Jitendra,

      Yes, this is possible. If you’d like an explanation of how, let me know.

      Best,
      @MsGreene

      Added:
  304. Edward

    Hello Dr. Greene,
    I have two children both O- however my wife and I are both O+
    I understand your explanation above how this is made possible.
    Just wondering though is there also possibilities for blood types to
    skip generation or be inherited? Just asking because my Mother is also
    an O- like my two kids. Im almost certain her parents (my grandparents)
    are both RH+
    Thanks!

    Added:
  305. Donna

    I am a B+ and I have a daughter that is B- I do not know her fathers blood type but what would that be? She is now pregnant and they are telling her she may need a shot at different times during the pregnancy because of the negative. I am just wondering where that negative come from and how is that related to pregnancy. The doctor asked If I had to have a shot at pregnancy but I think Id remember that.

    Added:
    • Donna

      Thank you so much we will look at the article.

      Added:
  306. Claire C

    Hi Dr. Greene,

    My Mother and Father are both A positive (I think) and I am O negative – is this possible?

    Added:
    • Cheryl Greene

      Claire,

      Yes, it is possible for two parents who are A+ to have a child who is O-.

      If you’d like an explanation, please let me know.

      Best,
      @MsGreene
      Co-founder & Executive Producer DrGreene.com, Mom

      Added:
      • Nona

        I would like an explanation, please. I had twin daughter – one is O negative and the other is O positive. Both myself and their father are A positive. Also, when they were born, I am pretty sure the Dr’s told me they were A positive. I am confused. They are 33 yes old.

        Added:
        • Marie

          Hi, my blood is rh b- my half sister is rh o- we have same mum different dad, my mums sister is rh o- aswell, but she is my mums half sister , they have same mum different dad. I have 3 children who are all positive as I had anti d with all of them? Is that right, where does the rh- come from?

          Added:
  307. Anna Win

    Hello
    Im O negative and my parents are A and/or B positive. Im doing my family tree and so far discovering that im the only one with this blood type. Is this possible? As neither of my parents/family carry my blood type.
    There is currently no evidence of as to how this is possible and i need it cleared up for myself to know. I only discovered my blood type after suffering two miscarriages and being told this is a factor. Please. I need answers, even if its not good.

    Added:
  308. Qasim ali

    My blod group is ab- and my wife blod group is o+ it is possible we have a child with o- or its not possible

    Added:
    • Cheryl Greene

      Qasim,

      Our current understanding of science is that it is not possible for one parent to be AB and his or her child to be O.

      It is not unusual for one party to have a different blood type than thought. It is wise to have all blood types retested before jumping to any conclusions.

      Best,
      @MsGreene

      Added:
      • Anonymous

        Hi Cheryl Greene, my dad was AB+ and my sister is O- … test were done years ago and he is definitely her father …

        Added:
  309. Jillian

    Thank you for this post!! I really enjoyed reading it! My mom is A- and my father is O+. I ended up O-and RH+. My mother is RH- and my father is RH+. Is there a possibility for me to pass on RH- as an active or recessive gene to my 3 daughters?

    Added:
    • Stephanie

      Hello, I just found out that one of my daughters is RH+ and I’m O+. Can her father be any blood type?

      Added:
      • Cheryl Greene

        Stephanie,

        You haven’t provided enough information to be able to provide a meaning full answer, but I can say that if you are Rh+, you can pass down the D antigen, and your child could be Rh+ even if her father was Rh-.

        Do you know your blood type?

        @MsGreene

        Added:
        • Stephanie

          Yes, I indicated that I am O+ and my daughter is RH+. My question was if her father could be any blood type? I don’t know her father’s blood type.

          Added:
          • Cheryl Greene

            Hi Stephanie,

            Sorry, I meant, “do you know HER blood type?” If you know her blood type, I can tell you the possibilities for her father, but without that, I can not.

            Best,
            @MsGreene
            Co-founder & Executive Producer DrGreene.com

            Added:
        • Stephanie

          Dr. Greene, I did say what HER my daughter’s blood type is… RH+

          Added:
          • Cheryl Greene

            Stephanie,

            There are two part to the name of the type, the first is identified by A, B or O. The second is identified by + or – and is referred to as Rh+ or Rh-. But without the letter, that’s an incomplete type. Your type is O and is Rh+. You know that hers is Rh+, but is it A+, B+, O+ or AB+?

            Dr. Greene explains both in Blood Types 101: An Introduction to ABO Blood Types and the Rh System.

            Sorry we’re having trouble communicating about this one.

            @MsGreene

            Added:
  310. Sapphire

    My mom is O positive, my dad is A positive. My brother and sister are both O positive. Im O negative. Just wanna ask if it’s possible? Thanks.

    Added:
    • Cheryl Greene

      Sapphire,

      Yes, it’s possible for one parent to be O+, the other parent to be A+ and their children to be O+ or O-.

      If you’d like an explanation, let me know.

      @MsGreene

      Added:
  311. Manoj rana

    I have a O+ blood type. My parents are B+ (mother) and B- (Father). Is this outcome possible?

    Added:
    • Cheryl Greene

      Hi Manoj,

      Yes, it is possible for one parent to be B+ and the other B- and their child to be O+.

      If you’d like an explanation, let me know.

      @MsGreene

      Added:
  312. Manoj

    I have a B- blood type. My parents are O+ (mother) and B+ (Father). Is this outcome possible?

    Added:
    • Cheryl Greene

      Manoj,

      Yes, it is possible for a child to have B- blood if one parent is O+ and the other is B+.

      Best,
      @MsGreene

      Added:
  313. Helen

    Hi Dr Greene,My sister is o+ and the husband is b+ ,then there son is o- ..is it possible. Thsnks

    Added:
    • Cheryl Greene

      Helen,

      Yes, it is possible for a child to be O- if his or her parents are O+ and B+.

      If you’d like an explanation, let me know.

      @MsGreene

      Added:
  314. toya

    Hi good day
    I’m B+ and my husband is O+ and my son A+ blood is this possible…
    my son looks like both of us so its confusing
    and now his parents are questioning if thats there grand son

    Added:
    • Cheryl Greene

      Toya,

      Our understanding of the current science is a B+ parent and an O+ parent can not have an A+ child.

      There is a good chance one of you has a different blood type than you think. Retesting is the next step.

      If that is inconclusive, DNA paternity testing is 99.999% accurate.

      Best,
      @MsGreene

      Added:
  315. Lynne

    Hi there,

    My mother is A+ and my father AB+, and I am A-

    Is this possible? ?

    Added:
    • Cheryl Greene

      Lynne,

      Yes, if one parent is A+ and the other is AB+ it is possible for their child to be A-.

      Let me know if you’d like an explanation.

      @MsGreene

      Added:
  316. Alison McGinn

    Hi Dr Greene, My mothers’s blood group was A & my blood group is Rh A negative. I don’t know my father but what do you think his blood group would have been?
    Thank you

    Added:
    • Cheryl Greene

      Hi Alison,

      If one parent has type A blood and his or her child has type A- blood the other parent could be A+, A-, B+, B-, O+, O-, but not AB+ or AB-.

      I hope that’s helpful.
      @MsGreene

      Added:
  317. Aman

    hello Dr Greene, my both parents are B+ and we children have O+ AB+ and AB- is it possible or we were exchanged in hospital

    Added:
    • Cheryl Greene

      Hello Aman,

      If two parents are B+, they can have children who are O+, but not AB+ or AB-.

      You might have been exchanged at the hospital or perhaps one of your parent’s blood types is different than he or she thinks it is. This is not uncommon. Perhaps the test was in error or recorded in error. For instance if one parent was B+ and the other was A+ or A-, they could have children who are O+, AB+ and AB-.

      I hope that’s helpful.
      @MsGreene

      Added:
  318. Emma Morrison

    Hi my mum is Ab- and my dad is Ab+ but I am O+.
    Am I right in thinking that is not possible.

    Added:
    • Cheryl Greene

      Emma,

      Our current understanding of science is if one parent is AB- and the other is AB+ they can not have a child who is O+.

      Sounds like the next step is retesting or discussing with your parents.

      Best,
      @MsGreene

      Added:
  319. Winter

    Hello Dr. Greene.. I was rather confused about my blood type.. My father is O+ and my mother is B+ and all my brothers and sisters are B+ like my mother.. how can I have B- ??

    Added:
  320. Lacey

    How do I figure out if me and my parents have the same blood type

    Added:
    • Cheryl Greene

      Lacey,

      All three people need to have their blood tested.

      Best,
      @MsGreene

      Added:
  321. Chase

    My dad is o+ and my mom is a+ and I am a- is that possible

    Added:
    • Cheryl Greene

      Chase,

      Yes, it is possible for a child to have A- blood if his parents are O+ and A+. If you’d like further explanation, let me know.

      Best,
      @MsGreene

      Added:
  322. Ammu George

    Hello Dr Greene,
    My mum is O- , my dad is B+, and my older sister is O-. However I am B-, is this possible, are they my biological parents? Please clarify this for me. :)
    Many Thanks

    Added:
  323. Angie

    Hello, my question is this my son is O negative and his ex girlfriend is also O negative . She recently gave birth to a O positive baby girl and refuses a dna test but i have been under the assumption that two O negative RH negative parents can not make a positive child.

    Added:
    • Cheryl Greene

      Hi Angie,

      Our current understanding of science is that it is not possible for two O- parents to have a child who is O+.

      DNA paternity tests are 99.999% accurate.

      Best,
      @MsGreene

      Added:
      • Angie

        Thank you that was my understanding also.

        Added:
  324. steph

    Can an a+ mother and an a- father conceive an o rhesus negative blood group child

    Added:
    • Cheryl Greene

      Hi Steph,

      Yes it is possible for an A+ mother and an A- father to have an O- child. If you’d like an explanation, let me know.

      Best,
      @MsGreene

      Added:
      • steph

        Hi i got it wrong my mum is a- and my father is a+ blood group is it possible for me to be o rhesus negative

        Added:
        • Cheryl Greene

          Hi Steph,

          Yes, it is possible for a child to be O- if his or her parents are A- and A+.

          If you’d like an explanation, let me know.

          Best,
          @MsGreene

          Added:
      • Ali

        Dear. If motherb is A + and baby is AB -. What possible groups father may have

        Added:
        • Cheryl Greene

          Ali,

          If the mother is A+ and the child is AB- the father is either B+ or B-.

          If you’d like an explanation, let me know.

          Best,
          @MsGreene

          Added:
  325. Ammu

    Hello, I am only 13 and would like to know more about all of this bit, i cant seem to understand everything that has been written, if it is possible could you translate it inot simpler terms.
    Thank you
    Ammu

    Added:
    • Cheryl Greene

      Ammu,

      Each person has two alleles that make up a blood type.

      The most common alleles are labeled A, B and O.

      Each parent passes one allele down to his or her child, so the child’s blood type is determined by the type passed down from both parents.

      Does that help?
      @MsGreene

      Added:
      • Ammu George

        Thank you Dr Greene! That’s really helpful, that will really help me in my upcoming exams!
        Once again thank you very much!
        Ammu

        Added:
  326. gittik

    Hi my blood group is a- and my mother blood group is a+ and my father is b+ its possible.

    Added:
    • Cheryl Greene

      Gittik,

      Yes, this is a possible combination.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene

      Added:
      • Karon McMakin

        I’d like to have the explanation of how an A+ and B+ have a child with A- blood. That’s my situation and we’ve always been curious!

        Added:
        • Cheryl Greene

          Hi Karon,

          Blood types are comprised of two alleles. The common alleles are A, B, and O. These combine to make up blood type A, B, O and AB.
          – If someone is A, he or she can have two A alleles (AA) or one A and one O (AO).
          – If someone is B, he or she can have two B alleles (BB) or one B and one O (BO).
          – If someone is O, he or she can only have two O (OO).
          – If someone is AB, he or she has one A and one B (AB).

          Likewise, the Rh system is comprised of two alleles. Positive (+) and negative (-).
          – If someone is Rh+, he or she can have two positives (++) or one positive and one negative (+-).
          – If someone is Rh-, he or she can only have two negatives (- -).

          Each parent passes down one allele for blood type and one for Rh. In the example you give:
          – The parent with type A blood passed down an A.
          – The parent with type B blood passed down an O.
          – Each parent passed down a negative allele.
          – The child would be type AO, Rh- or A-.

          Hope that helps,
          @MsGreene

          –

          Added:
  327. Tyler

    My father is AB+ and my mother is o+ my blood type is o- is that possible?

    Added:
    • Cheryl Greene

      Tyler,

      Our current understanding of science is that it is not possible for one parent to be AB+, the other to be O+ and their child to be O-.

      Before you jump to any conclusions, it’s wise to talk to your mother about having everyone tested again. It’s not uncommon for one of the types to be different than what people think it is.

      Best,
      @MsGreene

      Added:
  328. Cheryl Greene

    Our current understanding of science says it is not possible for two parents with Rh- blood to have a child with Rh+ blood (though two parent’s with Rh+ blood can have a child with Rh- blood). Dr. Greene explains how and why in this Q&A Blood Types 102: The Role of A, B, O, and AB Groups In Determining Paternity.

    Before you jump to any conclusions though, keep in mind that it is not uncommon for one of the three blood types to be different than what is thought. This can happen because a test is in error or it is recorded incorrectly.

    If, after checking for accurate blood types, you are still concerned, it is possible to have an at home DNA Paternity test. You can even order these online. Some are valid for legal purposes and others are less expensive, but not used for legal purposes. Both tests claim to be 99.999% accurate.

    As Dr. Greene says, “I realize that the circumstances that prompt a person to undergo paternity testing are often difficult. I hope that whatever you want turns out to be true. Even more, I hope that whatever turns out to be true becomes something that you learn to want.”

    Best,
    @MsGreene

    Added:
  329. Mandy

    My Mother is A+ and my Father is o+. I am A-. Is this possible ?

    Added:
    • Cheryl Greene

      Hi Mandy,

      If one parent is A+ and the other is O+, is it possible for their child to be A-. No problem at all.

      If you’d like an explanation, let me know.

      Best,
      @MsGreene

      Added:
  330. Mara

    I have always had my suspicion that my “birthparents” arent actually by birthparents. I grew up in the foater ayatem and upon research found out my parents blood. My father according to his bloodcard is an A- while my mother according to her bloodcard is O-. I am a B+. I also do not share resemblance to either parent.
    We have all been tested by bloodsource and given cards for medical purposes. How is this possible?

    Added:
  331. Lisa

    My Mom is O+
    My Dad is O+
    Both my siblings are O+
    I’m A+
    Is this possible?

    Added:
    • Cheryl Greene

      Lisa,

      Our current understanding of science is that two O+ parents can only have O+ or O- children.

      It is not uncommon for one or more of the individuals in question to have a different blood type than they think they have. This can be because the test is in error or it was recorded incorrectly. It’s wise to talk to your mother about retesting before jumping to any conclusions.

      Best,
      @MsGreene

      Added:
  332. Jo

    I am O negative and my husband O positive . But we have child of B + .. Is that possible?

    Added:
    • Cheryl Greene

      Hi Jo,

      According to our understanding of the current science, this is not a possible combination. There are two reasons for this outcome:
      1) One of the blood types is not what you think it is.
      2) The person you think is the father of this child, is not.

      If you’re sure your husband is the father, it’s time to get everyone’s blood type retested.

      Best,
      @MsGreene

      Added:
  333. Lori

    hi , My mother is A positive and my father is O positive but I am AB positive. how is this possible. I am too confused

    Added:
    • Cheryl Greene

      Lori,

      Our understanding of the current science is that a parent who is A+ and a parent who is O+ can not have a child who is AB+.

      Before you allow your confusion to become an accusation, it’s wise to have all three party’s blood retested. It’s not uncommon for one of the three types to be different than what people think it is.

      I hope that helps,
      @MsGreene

      Added:
  334. D Green

    I’m not sure on my parents blood types but I’m A+ and my sister is A-. It’s this any indication that we may not be full sisters?

    Added:
    • Cheryl Greene

      D,

      It is very common for two siblings to have different Rh factors. It is not an indication that you may not be full siblings.

      @MsGreene

      Added:
  335. Alexis

    Hi, I am wondering of both of my parents are a+ ,can they have a child who is o-?

    Added:
    • Cheryl Greene

      Yes, it is possible for two A+ parents to have an O- child. If you’d like an explanation, let me know.

      Best,
      @MsGreene

      Added:
  336. Dexie

    Hi. If my husband and I are both O blood type, is it possible to have a child with A blood type? is it possible to get the child’s blood type on grandparents?

    Added:
    • Cheryl Greene

      Dexie,

      Our current understanding of science is that it is not possible for two O blood type parents to have a child with A blood type.

      Some times children have different blood types than their parents and the same blood type as grandparents, for instance two type A or two Type B parents can have type O children. Here’s why:
      A is dominant
      B is dominant
      O is recessive

      Blood types are comprised of two alleles:
      Type A = AA or AO
      Type B = BB or BO
      Type O = OO

      This means:
      Type O (which is made of two Os) can only pass down O
      Type A can pass down A or O
      Type B can pass down B or O

      Hope this is helpful,
      @MsGreene

      Added:
  337. kim

    hello,
    my mother is O+ and my father is B+ .can they give birth to a AB-

    Added:
    • Cheryl Greene

      Kim,

      Our current understanding of science is it would NOT be possible for an O+ parent and a B+ parent to have an AB- or AB+ child.

      If you’re interested in the reasoning behind this let me know.

      In the meantime, remember blood type tests can be in error or reported in error. It’s wise to retest both parents and child before making any judgements.

      After testing, if further information is needed, a DNA paternity test is a good option. It offers much more information than blood type alone.

      Best,
      @MsGreene

      Added:
  338. Deborah

    Please help if you can concerning the rh A negative mother and Rhode An positive father. My father loved me very much but my mother did not. She loved my sister who was 12 years older. It would not upset me at all if she weren’t my biological mother. Please help if you can. When my blood was typed and it came back O positive the doctor told me it was impossible due to my parents blood type. Are the doctors correct.
    Thank you for your home help.
    Deborah

    Added:
    • Cheryl Greene

      I am unfamiliar with “Rhode An positive” blood type. Might this be a typo? If so, please correct.

      Added:
    • Valerie

      Can a 0+ and b- be full siblings ?

      Added:
      • Cheryl Greene

        Yes, this is possible.

        If at least one parent is type B and the other is not type AB.

        Best,
        @MsGreene

        Added:
  339. Deborah

    Hello,
    Please help. My mother was rh A negative and my father was rh Ab positive. My sister was rh Negative and even though she had the prenatal injections for rh Negative, she had 4 miscarriages. I have O positive blood. How is this possible ? Could I possibly have O positive blood from these parents? I am 60 yrs of age and there has always been a possible discrepancy in the family. Please help if you can.
    Thank you

    Added:
    • Cheryl Greene

      Deborah,

      Our current understanding of science is that a person with AB blood type can not have a child who is type O. The reason is all people with type O blood have an O from each parent and someone with AB blood type does not have an O to pass down.

      We always remind folks that blood type test results can be in error or can be recorded and passed down in error. It’s wise to retest when possible. It sounds like that may not be an option for you.

      If there is a discrepancy, might it be that you were a very wanted child, but your parents were never comfortable discussing this with you?

      Hope this helps,
      @MsGreene
      Co-founder & Executive Producer, DrGreene.com

      Added:
      • Deborah

        Thank you so much. Is it possible my father could have the rh An positive and my real mother was an O positive? My father loved me very much but unfortunately my mother did not feel the same. You have answered a lifetime of question. Bless you for your help.

        Added:
  340. Ara

    My father is O blood type while my mother is AB blood type and ihv learned in school that its impossible for AB and O to have O or AB for their kids but two of my brothers have O blood type? I’m so confused. Is this possible?

    Added:
    • Cheryl Greene

      It is not considered possible for one parent to have AB blood type and the other to have O blood type to have children who are either AB or O.

      We know our understanding of science is constantly growing, so we may find our current understanding is wrong. It is also possible that one or more tests are in error or were recorded in error.

      Before jumping to any conclusions, it is wise to have everyone’s blood tested again. If there is still a question, DNA paternity testing is much more sensitive than blood type testing.

      Best,
      @MsGreene

      Added:
  341. Latona

    I’m A positive my daughter is B positive (so I was told when she was 4 days old) what would father blood type be.

    Added:
    • Cheryl Greene

      If one parent is A+ and the child is B+, the other parent could be either B+ or B-.

      Added:
  342. Snowflakes

    I am type AB from our blood typing in school but my mother is type B and my father is type O. I got some of my mother’s features and as well as some features from my father’s side but still, because of the result of our blood typing in school I started to feel curious and I want to find the truth by myself. I hope you could help me THANKS ??

    Added:
    • Cheryl Greene

      It sounds like you have information about how blood types are inherited. Whenever there is a discrepancy, I encourage retesting of both parents and the child. It’s not uncommon for one of the three results to be in error or to have been recorded in error.

      Added:
  343. Daniel Ssemambo

    I am B- and would like to know if possible to have a DNA test carried out on my children and what can prove they are mine?

    Added:
    • Cheryl Greene

      DNA paternity testing is now easily avaiable.

      Here is a link to an option for Paternity Testing. They offer a home test for under $200. This can’t be used for legal purposes, but can give you paternity information.

      If you need to determine paternity for legal reasons, the price is higher (around $450) and you have to go to their location.

      We are not connected in any way to this lab. There may be others that offer more affordable options or have labs closer to you. Before you decide to do paternity testing, you may want to look online for other options.

      Added:
  344. bill

    you are nothing more than a commie if you have to censor my question. you must belong to the media slugs. I HAD ASKED YOU NICELY …YOU SHOULD DELETE THIS SITE .

    Added:
      • Shawn

        Dr green,
        I have 0- type both my parents have A+ and my older brother has A+. Is that possible?

        Added:
  345. STBAT

    I am the daughter of a mother who is O+ and a father who is AB-. Upon going through nursing school I was told this is not possible. My father was in the military and his blood type is on his dog tags. I am sure he was typed correctly. My Anatomy and Physiology teacher saw my type along with the doctor from my five pregnancies. They all typed me as O-. I have read that on rare occasions that AB parents can have an O child. Can you please explain this better to me?

    Added:
    • karan

      IT is possible to have O-ve just read the article. since your parents have such diverse blood group it is possible for you , too have any blood group based on the combinations possible, since your mom could be O positive having the (+ -) rh factor, so you could be O+ or –

      Added:
    • Brooke

      Hello, I have the same predicament. My father is now deceased, but he told me before dying a few years ago that he had the “weird, rare type” that I do, which is AB neg. My mother swears up and down that she is O pos. There is an extremely rare type of AB that is inherited solely thru paternal lineage, but I am not sure of the exact name…it’s on the tip of my tongue, tho. Please email me if you find that this is the case with you, as only a handful of us are thought to exist, and I have found that I have very special connections with others of our type to a point of not minding contact from a veritable stranger…I know it’s fine.

      Best,
      Brooke

      Added:
      • Cheryl Greene

        Brooke,

        The type you are looking for may be Bombay, which is hh, but is reported as O because the blood tested for ABO blood type can not record hh.

        If you think this is the case, talk to your doctor about a specialized test for this blood type as it does not show up using the normal ABO blood type tests.

        I hope that helps.
        Best, @MsGreene
        Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

        Added:
  346. Charles

    Is it possible for two Os to make an A baby?

    Added:
    • Cheryl Greene

      Based on our current science, that is not considered possible. What is possible, is for one of the three blood types to be taken in error, reported incorrectly, or remembered differently than was reported.

      Added:
  347. Gene

    My dad is O blood group and my mother is B. Mine is A. Is it possible or can it be that my dad isn’t my real dad?

    Added:
    • Cheryl Greene

      Based on our current science, that is not considered possible. What is possible, is for one of the three blood test to be in error, reported incorrectly, or remembered differently than was reported.

      Added:
  348. T'Anna Morris

    I just had a baby about 2weeks ago and I found out my son is b postitive so is his father but the father’s parent’s are both o negative , I am o postive blood what blood type does it make it to a b postitive.

    Added:
  349. Punam Khandagale

    My blood group is B (-) ve my wife’s blood group is O (+) ve, but my daughters blood gruop is B + ve,
    can it be possible?

    Added:
    • Cheryl Greene

      Punam,

      It is possible for one parent to be B- and and the other parent to be O+ and their child to be B+.

      The possible children from one parent who is B- and the other parent who is be O+ are:
      — O+
      — O-
      — B+
      — B-

      I hope this is helpful.

      @MsGreene

      Added:
  350. Sheila

    My dad is O+AND I’M B- WHAT BLOOD TYPE WOULD MY MOTHER BE. OR IS MY DAD TRULY MY DAD

    Added:
  351. MK

    Recently I have found out that my blood type is A negative and it’s rare but my fathers blood type was O, both parents have given me different versions of how I was born and I am starting to suspect that something doesn’t add up. My mother has passed now and I don’t know her blood type, and I don’t know how to obtain this information as I come up against a brick wall, where would I go to find out about my mothers blood type and where do you go to, to get a DNA as it’s very unsettling to me to find out that two parents are not telling me the truth about my birth. My mother tells me I was born breach and she didn’t see me for 10 days after the birth, she didn’t know if I was alive or dead I found it very strange that she would leave it 10 days and didn’t ask a nurse how her baby was because she said there were at least 14 doctors at my birth because I was a breach birth and their had been difficulties. My father on the other hand told me he picked my mother and I up from the hospital four days after my birth and I was not born breach, where can I go from here!! very confused.

    Added:
  352. Kara

    I don’t know my mothers blood type, but my father was RH negative. Could I be RH negative too?

    Added:
  353. Tammy

    Can a father b positive and a mother a positive have a ab negative child? Or can a father b positive and a mother a negative have a ab negative child?

    Added:
    • Cheryl Greene

      Tammy,

      In his article Blood Types 101: An Introduction to ABO Blood Types and the Rh System Dr. Greene explains how this is possible. Here is an excerpt from that article:

      In this system the positive are dominant over the negative. Thus if your genetic type is ++ or +-, your blood type will be Rh positive. Only if your genetic type is — will you be Rh negative. This means that if both parents have Rh+ blood with the +- genes, they could have children who are ++, +-, or – -. In other words, their children could be either Rh positive or Rh negative. Children who are Rh negative can have parents who are either Rh positive or Rh negative.

      This is why two parents who have O positive blood could easily have a child who is O negative. In fact, most children who are O negative have parents who are positive, since the +- combination is so much more common than the – – combination.

      I hope that’s helpful,
      @MsGreene

      Added:
  354. Noosha

    Hi my parents they both have O+ blood and mine is B+. How is it possible?

    Added:
    • hassan

      Hi my parents they both have O+ blood and mine is B+. How is it possible?

      Added:
      • Jacob

        Current scientific studies examine that two O + parents cannot have a B+ child. Parents with O+ can only yield children with O blood types, positive or negative. In order for a child to yield B type one parent must be B type. It’s likely that the information was erroneous. Suggestions would be to to reexamine all parties blood types.

        – Jake

        Added:
  355. Jeeva

    Is it possible for a child to have o negative blood group if parents have b positive and o positive blood group

    Added:
  356. DeBorah

    Is it possible for two A++ parents have an 0–baby?

    Added:
  357. jai

    Is it possible for a child to have a b- blood group with parents having o+ & A+ group?

    Added:
  358. shani woolford mclaughlin

    Hi there im AB Rhesus Neg blood group and my mum is A Rhesus Neg what would be my fathers type plz x

    Added:
    • Cheryl Greene

      Hello Shani,

      If one parent is A- and the child is AB- the other parent can be B-, B+, AB- or AB+.

      Hope that helps,
      @MsGreene

      Added:
  359. Mizz Mek

    I am AB- (although for some reason I turn up B- on some tests – this is what I am truly interested in understanding although the discrepancy of my parents blood type tested and retested – makes my birth and bloodtype a supposed impossibility) please note: both my parents are O+
    We have tested and they are both my parents. (Not just one time, but several times, as everyone scratches their head in confusion). We even went as far as to test sibling uncles and aunts – with no luck in finding an answer to impossibility.
    I have had no transfusions and both my parents have not had blood transfusions.

    My question is not so much to the impossibility of me being born an rh negative, but the potential changing of the AB to B negative at various tests. We’re talking I’m almost 50 – and I’ve given birth to a daughter with Rhogam, etc.

    I don’t think the testing points are making mistakes, so wondering if there is something unusual about me – maybe food I eat or otherwise, that can be causing this variance? Hormones? Anything? I’m a single child to my mother and father so no siblings to this bloodline.

    My ex is an O+ and I believe my daughter – at last count – was A+.

    Thanks – I don’t want to seem like and idiot, or that I’m lying – because with all the strange reactions I’ve gotten, I realize this is an anomaly. However, it is what it is, and I’m wondering if perhaps it’s that the tests are not sensitive enough… or there is some sort of antigen blocking agent that causes it – or if maybe I have too much iron or something in my blood that it is causing this reaction.?

    I’ve always just assumed that someone screwed up somewhere. But we’re talking at least 15 tests = 3 pregnancies – where I lost what I assume was + factor child. I almost lost my daughter at 3 and a half months -and had multiple shots of rhogam – and well there is a long story after that – had to go on bed rest last month.. and I felt sicker than snot.

    But anyhow – I’m curious about all of the potential possibilities for my blood type to sometimes come out B- and sometimes as AB-…. And while my mom and dad are both o+ they are definitely my actual parents.

    Added:
    • Cheryl Greene

      Dear Mizz,

      I’ve said on this board multiple times, our science is limited. We know what we know, but we have no idea what we will learn in the future. Who knows, we may find a specific type that changes in certain situations, such as pregnancy.

      Have you presented your case to a geneticist at a major research hospital or university, such as Stanford or Harvard? You may be of interest to their studies and they may be able to help you find answers.

      Best,
      @MsGreene

      Added:
    • Sarah

      If you haven’t already tried it, buy a blood type test kit and try taking the test yourself and see what results you get.

      Added:
  360. Joseline

    DR.GREENE,
    My mum blood type is A+ and my dad is o+ but i am A- how possible is it please .
    Please help to me understand

    Added:
  361. SM

    My mom Isaid a b+ and my dad is a b+. But I’m an A- blood. Is that possible? My Dr told me that my dad can’t be my dad because of my blood to get dna. Test

    Added:
    • Cheryl Greene

      Dear SM,

      In cases like the one you described, it’s wise to have everyone retested before jumping to any conclusions. It’s very possible for one of the three types to be different than what you think it is.

      If the re-tested results come back the same, a DNA test can tell you if the man you call dad is indeed your biological father.

      I hope that helps,
      @MsGreene

      Added:
  362. Mousey

    I am O neg; my husband and father of our children is O pos. First born is A+. I’m told this is impossible, but there is no other answer: no affairs or other person could be father???

    Added:
  363. sanjay

    Hello My wife blood group is O-ve and my Blood group is O+ve and my daughter’s blood group is O-ve.

    Is it possible? .

    Added:
    • Cheryl Greene

      Sanjay,

      Yes, this is a possible outcome. But you need to be aware of the risks associated with subsequent pregnancies.

      Please see Dr. Greene’s Q&A How To Determine and Manage Rh Incompatibility. He explains that the first pregnancy is not an issue, but if not properly treated, it can be an issue.

      I hope that’s helpful,
      @MsGreene

      Added:
  364. Yvette

    Hi my sister and I were born in the 1950’s. My mum was O negative my dad was O positive. Both us sisters are O positive. Mum was sensitised on first pregnancy and my sister was born heavily jaundiced. Second pregnancy was no problem, with me being delivered as a home birth. Is this possible as I assumed the antibodies in my mums blood would have attacked me?

    Added:
    • Yvette

      I realised i have not explained things so good. To clarify, my mum only had two children, me and my sister. Both of us were O positive. My sister suffered jaundice at birth as my mum had become sensitised at some stage but I suffered no ill effects from antibodies, even though my blood would not have been compatible with my mums O negative type blood. Thanks, Yvette

      Added:
    • Cheryl Greene

      Hi Yvette,

      If a mother is O-, she typically does not have an issue with the first pregnancy and is treated immediately. This keep her from having a problem with subsequent pregnancies. For all the details see How To Determine and Manage Rh Incompatibility.

      Best,
      @MsGreene

      Added:
      • Yvette

        Hi and thank you for responding but I think you have misunderstood. My mother was sensitised during her first pregnancy and as a result my sister was born heavily jaundiced. As this was the 1950s there was no treatment and so when my mum got pregnant with me, another O positive baby I thought the antibodies should have attacked me but they did not.

        Added:
  365. Lydia

    HELLO,
    When I found out I’m A+ I questioned my mother her blood type is O+ and my so called father is O-. My brother and sister are O’s. We keep questioning her but denies someone else is my father. I need answers been trying find out for 15 years. Please help ?

    Added:
    • Cheryl Greene

      Have you had your blood types re-tested? I know that’s an obvious question, but, in a scenario like this, it’s not unusual to find someone’s type is different than he or she thinks it is.

      Added:
  366. Samantha

    Can 2 A positive parents make a O negative child? Can someone please help me understand.

    Added:
  367. Sass

    Can I be a B Rhesus Negative and my Siblings be an O positive. My mum said she was A+ . I could potentially be my step father’s child? By as my father, step father and mother have passed away there is no way of checking their blood group. What are the % probabilities do you think?

    Added:
    • Cheryl Greene

      Hi Sass,

      Blood types are made up of two alleles. One comes from each parent.

      Here’s how that can look:
      — O = OO
      — A = AA or AO
      — B = BB or BO
      — AB = AB

      Here is one scenario that would explain what you’ve outlined:

      — Mum = AO
      — Dad = BO
      — Child 1 gets an O from Mum and a B from Dad
      — Siblings get O form Mum and O from Dad

      Additionally, if Dad were Rh-, each of his children would have a 25% chance of being Rh-.

      Basically, what you’ve outlined is possible.

      Hope that helps,
      @MsGreene

      Added:
  368. Eric

    Hi. My father lives in spain he wanted me to come live with him there. During the process of the paper work, a DNA test had to be done to prove if truely am the real son of my father which they took some tissues from my mouth . just yesterday the results came out and my DNA matched totally different from my father’s. I had a talk with my mom to know whether she had an affair with another man whiles she was with my father. She was clear to me that such thing never happened and I believed she was telling me the truth. I also believe my father is my real father because, there are a lot of resemblance between me and my father’s mother that is my grandmother but the DNA test proves the man I believe is my father is not. Please can there be any possibility that such thing can happen. I really need a quick reply because we have only one month to appeal to the Spanish embassy.

    Added:
  369. Jalaj Gupta

    My parents have B+ blood group. And my blood group is A-.
    Is it possible that am adopted?

    Added:
  370. Kim Smith

    My mother has O negative blood. she does not know either of her parents blood types. What are the possible type and rh factor combinations?
    If it helps, I am B positive and my father is B positive. I am the second child of my mother and father, my 3 younger siblings (same father) are all O negative. My mothers first child was adopted out (different father)and do not know blood type.

    Added:
  371. Thea Weiss

    Years ago when I was in my 20’s (I’m 61!), I accused my parents of adopting me because I am AB- and my Dad is O. He knew because of blood typing in the army in WWII. I knew because in my high school biology class we were allowed to test for our blood types. I was, at the time, a lab tech at Downstate Medical Center in Brooklyn, NY. I was sure my parents had lied to me, and was very upset. They were, of course, angry when I confronted them about it. Afterwards, a biochemist told me that there is actually a 1 in 10,000 chance of a mutation in the proteins on the blood cell surfaces that can make it possible for an O parent to have an AB child. What is the science (reference?) behind this? Thanks, from “a Mutant” (I think)!

    Added:
    • Jan C

      Both my parents have O blood andso does my siblings, I’m the only one with B+ blood type. However my question is there anyway the man I call my father.. My father???

      Added:
      • Akeeme Emanuel

        Hi if it helps my self and my baby mother is o positive and my son is B

        Added:
    • Sarah Wheeler

      Wow, just like me. I wanted to know how and why it’s possible that my (Dad is O+) Mom is AB+ and I am O+. It says everywhere I’ve looked that it is impossible. And I’m confused.

      Added:
    • Legendary

      I was wondering same but not negative positive could I have AB+ if my dad has O+

      Added:
  372. Cassidy S.

    My husband is A-, his ex-wife is O- and had to have the RhoGam shot. Their daughter is A+, their son is A- like my husband and the two children he had with me(even though I’m O+). His daughter is 23 and finally decided she wanted to know the truth, so my husband and she did a DNA test. It came back that my husband is 99.95% his daughter’s father. How is their daughter A+ blood type when both her parents are RH-?

    Added:
  373. Marilyn

    We adopted “twins”. Our daughter has B- and our son has A+

    Doesn’t matter to us, but is this even possible? What blood type might the biological parents have been?

    Added:
    • Cheryl Greene

      Hi Marilyn,

      Yes, this is possible. Since one twin is male and the other is female, they must be fraternal twins, not identical. This means, they have the same “rules” for blood types as other siblings.

      One possible combination that would result in one child being A+ and the other B- is one parent being AB+ and the other being AB-. In this case each child would have a 25% chance of having type A blood and a 25% chance of having type B blood (the remaining 50% would be AB). Each child would have a 75% chance of being Rh+ and a 25% chance of being Rh-.

      Hope that’s helpful or at least interesting.

      Best,
      @MsGreene

      Added:
  374. Carla

    Thanks for clearing up this long overdue answer to my question.

    Added:
  375. Patsy

    If a mother is O reh neg and father is O poss can you have an O reh neg child ?

    Added:
    • Cheryl Greene

      If one parent is O- and the other is O+ there is a 100% chance each of their children will be blood group O and a 6.25% chance each of their children will be Rh-.

      Please note that if a mother is Rh- and her partner is Rh+ there may be complications for pregnancies after the first one. Dr. Greene has written about that in this How To Determine and Manage Rh Incompatibility.

      Added:
  376. Tessa

    I’m having the same issue I’m o- they said hubby was ab+ and my first born b+ I want to say my second was the same but she could have been ab and I know he’s there father but it keeps saying impossible when I looked into it did they get something wrong

    Added:
    • Tracey

      … There is a 50% chance of having a child with B+ blood, if the parents are O- and AB+.

      Added:
      • Cheryl Greene

        This is correct.

        Type A and B are dominant and O is recessive.

        — If one parent is type O, that parent has two O alleles.
        — If the other parent is AB, that parent has one A allele and one B allele.

        Each parent contributes one allele to each child. In the above scenario,

        — Parent one will always contribute an O allele.
        — Parent two will contribute an A or a B allele.
        — So each of their children have a 50% chance of being AO, which is type A blood, and a 50% chance of being BO, which is type B.

        Hope this helps,
        @MsGreene

        Added:
  377. Marie

    Hi I’m a O+ blood group but the hospital said my daughter is AB how has that happen my partner doesn’t know his blood group but the charts say that it’s impossible for me to be her mother I know she my baby as she was born with a disability not something that could be swapped at birth. Our son is a O+ like me. When I question the nurse about her blood group she just said dad must be A or B.

    Added:
    • Cheryl Greene

      I’m guessing there is an error in her blood type. I’d ask to have it retested.

      @MsGreene

      Added:
  378. Kaitlyn Anson

    Hi, so my Mom is o+ and my Dad is A- and my blood is A-, and I’m the third child in my family, was I at risk of having the Rh factor when I was born, because I had nothing wrong with me when I was born.

    Added:
  379. Angela

    Hello there,
    My mother is Rh- and my father is O+ what would the out come be if it was my blood type

    Added:
    • Cheryl Greene

      Hi Angela,

      If one parent is Rh- and the other is Rh+, the child can be either + or -. Each child has a 75% chance of being Rh+ and a 25% chance of being Rh-.

      The blood group is determined by the blood group of each parent. Since you didn’t provide the blood group of your mother (A, B, O or AB) I can’t tell you what blood group you might be.

      Sorry I can’t be more helpful.
      @MsGreene

      Added:
  380. Sue

    Hi, my mother had rh neg blood and my father was b positive and i am o positive …….is this possible , i;m confused

    Added:
  381. mary hogencamp

    hi
    my mother has O+ an the one she says is my real father has B+ but i got A+ and my son took after me with A+ i was wondering if this was possible or could of been switched or adopted because the one thats suppose to be my full blooded brother has B+ and my half sister has O+ i seem to be the only one that has A+ blood type

    Added:
  382. Danielle

    If I am O- does that mean both of my parents are positive?

    Added:
  383. Sumanth

    I am B+and my wife is O+. we had a son of A+. How is this possible. Whether i am not his father?

    Added:
  384. Sarah

    My dad told me when I was 23 that he was NOT my biological father. He was drunk at the time…and says a lot of questionable things. My mother disputes this and says he is my father. But…as it turns out, everyone in my family has type AB positive blood type. I have O positive. Here is my question…could he have told me the truth? Is it possible for two AB positive parents with other children who are also AB positive to have an O positive child?

    Added:
    • Cheryl Greene

      Sarah,

      Our best science tells us two AB parents can only have A, B or AB children. The reason is each parent contribute one allele from their blood type to each child. AB parents can only contribute A or B.

      If this is important to you, DNA testing is the next step.

      I hope this is helpful.
      @MsGreene
      Co-founder and Executive Producer, DrGreene.com

      Added:
    • Michelle Heatherly

      He was telling u the truth it’s impossible

      Added:
  385. Misty

    Both of my parents are O positive blood types as well as my brother and sister and my blood type is A negative I visited a doctor and he told me that it was very rare for two positives to have a negative and the fact that I don’t have O blood type at all is what throws me off but my mother said my grandma on my father’s side has A negative blood would that factor in? I love my father with all my heart and he has been a wonderful father and I would hate to find out any different but on the other hand if I have some family out there that I don’t know about I would also like to know that. So I could possibly feel like I fit in somewhere my brother and my sister are nothing like me at all.

    Added:
    • Cheryl Greene

      Hi Misty,

      If two parents have Rh+ blood, there is a 6.25% chance that each of their children will have Rh- blood. Rare is a relative thing (pun intended), but seriously, when we say something is rare it means it doesn’t occur often, but not that it doesn’t happen.

      On the other hand, our best science says two parents with type O blood can only have children with type O blood. This does not mean the wonderful man you know as your father is not your father. It is not uncommon for blood types to be in error either from the lab or due to reporting or one of the three parties is remembering it differently than it is. I highly recommend discussing this with your mom and, unless she has something she wants to tell you, asking for all your blood types to be retested.

      Hope that’s helpful,
      @MsGreene
      Co-founder and Executive Producer, DrGreene.com

      Added:
  386. golara

    Hi . I need donor for pregnancy. I have find some one who has ab blood group and myhusband has positive o .so the child might be b or a.
    my blood group is positive b .
    We wont decide to tell anybody about this. So is ther any exception that o blood group and b blood group generate a blood group because we have to explain if it will happen ?

    Added:
  387. Christine

    Hi my mother is Rh negative o and I am Rh negative o but my brother is not Rh negative o though I’m not sure what group he is , our father has passed away but he was not Rh negative o is it possible he is not my father x

    Added:
    • Cheryl Greene

      Unfortunately, there is not enough information from what you’ve provided to be able to tell you if he was your father or not. Here is what I can say — according to our best scientific knowledge at this time, if one parent is O- and the child is O-, the other parent is either A-, B- or O-.

      I hope that’s helpful,
      @MsGreene

      Added:
  388. Anne

    My father is A, my mother AB, I am O
    Also both have blue eyes, mine are hazel

    This seems improbable that I’m biologically related to both…yes?

    Added:
    • Cheryl Greene

      Hi Anne,

      Here’s a very simplified answer to your question. Blood types are made of two alleles, each with a letter name. The most common (by far) are A, B and O.

      Here is how we name blood types:
      — Type A = A & O or A & A
      — Type B = B & O or B & B
      — Type O = O & O
      — Type AB = A & B

      Each parent contributes one allele to their child’s blood type. Therefore, if one parent is A and one parent is AB, each of their children could be:
      — Type A –> A & A
      — Type A –> A & O
      — Type B –> B & O
      — Type AB –> A & B

      To be a Type O the child would have to get an O from each parent and the parent with AB does not have an O allele to contribute.

      A word of warning — it is not uncommon for blood types to be different from what you think they are. Either one of the tests was done incorrectly, or there was a reporting issue or someone’s memory is wrong. Before you jump to any conclusions, ask to have everyone’s blood re-typed. An open conversation about this is often the best course of action.

      I hope that helps,
      @MsGreene
      Co-founder & Executive Producer, DrGreene.com

      Added:
      • Anne

        Thank you. I tried to have a conversation but my mom flipped out….

        Added:
      • Confused

        I recently discovered my dad is o negative. My mom is B+. I am AB+. Am I crazy or is it genetically impossible for my dad to be my dad? I have been retested and so has my dad. We are certain of our blood types.

        Added:
        • Cheryl Greene

          Confused,

          According to our understanding of science at this time, an O+ parent can not have a child who is AB+. If you think you’d like to pursue this further, you can have DNA paternity testing done. It’s now around $200 and you can order it online.

          I hope that’s helpful.

          Best,
          @MsGreene

          Added:
    • Sarah Wheeler

      Hi Anne, my mother is AB+ also and I still turned out to be O+ we are so special haha^_^

      Added:
  389. Rona

    My blood type is AB, my mother is AB, and my father have O blood type is it possible that i’m adopted?

    Added:
  390. Katie

    My husband and his ex wife both have ab- blood type so does his son he had with her. He’s concerned it may not be his so is that possible or would his son have had a different blood type like a positive or just a or b? I’ve been told usually all three pepole don’t have the same blood type but, then I’ve been told it is possible so we were confused.

    Added:
    • Cheryl Greene

      Hi Katie,

      Each person has two alleles that make up his or her blood type. Here is how that looks:

      Type A blood = One A allele and one O allele or One A allele and one A allele
      Type B blood = One B allele and one O allele or One B allele and one B allele
      Type O blood = One O allele and one O allele
      Type AB blood = One A allele and one B allele

      Each parent passes down one allele, so the child has one allele from each parent.

      In the case of two parents being AB-, each of their children have a 50% chance of having an AB blood type, a 25% chance of having blood type A, and a 25% chance of having blood type B. 100% of their children will be Rh-.

      Blood types are not considered a valid paternity test. DNA testing is much more accurate.

      I hope this is helpful,
      @MsGreene
      Co-founder and Executive Producer, DrGreene.com

      Added:
      • Katie

        Helps a ton! Thank you so much!

        Added:
  391. Dimple

    I’m confused now. So my Mother is O + and Dad is O, as well. My Brother is also O… but I’m B +

    what the heck happened? Is that my father?

    Added:
    • Cheryl Greene

      If both parents are type O, that means they have two O alleles and can only pass along type O.

      If one parent is type O and one is type B, they could have children who are type O or type B.

      In your situation it is wise to have all parties blood type tested again before jumping to any conclusions. It is not unusual to find that one of the types was in error either from the lab, in reporting or in people’s memory.

      Hope that helps,
      @MsGreene

      Added:
      • Michelle

        My husband and I are both type O and our first daughter was type O, but our second daughter was type A ? Strangely we shared the same blood disorder, and she inherited other things from her father,also we both have direct relatives with type A blood. We were all tested again for blood type. She is our daughter and we were amazed at the odds of this happening but it did !

        Added:
        • Cheryl Greene

          Michelle,

          I am struck by how little we know sometimes. Science is continually growing and with it our understanding. I’d love to hear the specifics of your results and how your geneticists are explaining the rare outcome.

          Best,
          @MsGreene

          Added:
  392. Amir

    My wife A negative and I have B negative blood type. Is it possible for our children to be B positive?

    Added:
    • Cheryl Greene

      Hi Amir,

      That is not considered a possible outcome. It would be wise for you all to have your blood type tests run again. This is especially important if your blood type is actually Rh+ instead of Rh-. It will be important to know this before considering having another child.

      Best,
      @MsGreene

      Added:
  393. Ann

    Last year I just founed out that my blood type is B blood type
    And my mother is o postive and my dad believes that he’s o positive
    But when my doctures told me that I was B and not O positive my mum and dad were both puzzled is it possible that my dad might not be my dad
    Can I do a home DNA test to fined out ??

    Added:
    • Jones

      It means that your mom and dad blood type allele is carrying a B. Even your siblings are all type o positive, that chance of you being a type B is completely normal. Probably one of your grandparents is either type AB or B.

      Added:
  394. miriam

    My blood group is A positive and I have sisters with AB negative my mother blood group is O positive is it possible for me and my sister to have the same father and if not what will be my father blood group

    Added:
  395. Melissa

    I just had a baby last week.. I am A-, daddy is O- but the baby is B-?? Is that possible or am I going to have to start proving myself and setting up DNA tests for his already skeptical family. He was in the military and says he knows his blood type is O- for sure.

    Added:
  396. sabrina

    I’m b+ and my ex husband is a + but my son is a + but my daughter is o+ how did that happen cause I like to know please cause it’s got me worried

    Added:
    • Cheryl Greene

      Blood types consist of two alleles. They are either A,B, or O (there are a few other types, but these are the common ones).

      – If mom is blood type B, that means she is BB or BO and will pass down either a B or an O allele.
      – If dad is blood type A, he is either AA or AO and will pass down either an A or O allele.

      In this case, the children could be:
      – OO which is type O
      – BO which is type B
      – AO which is type A
      – AB which is type AB

      In other words, it all fits.

      Hope that helps.
      @MsGreene

      Added:
  397. D.latha

    Hi,
    If both parents are o+ group, in five member children,3member children’s have o+,last two member children’s are A + ,is it possible….. My mother would n’t take treatment for pregnancy, all are normal deliveries at home…..so why this other blood group….pls give me advice…

    Added:
  398. Mimi La fleur

    Mom O + and Dad B + and brothers, O + _O + _O order, but I am A + Is this possible, I note the second son

    Added:
    • Cheryl Greene

      Blood types consist of two alleles. They are either A,B, or O (there are a few other types, but these are the common ones):

      – If mom is blood type O, that means she is OO and will pass down an O allele.
      – If dad is blood type B, he is either BB or BO and will pass down either B or O allele.

      In this case, the children could be:
      – OO which is type O
      – BO which is type B

      Before jumping to any conclusions, talk with your mom and consider retesting. It’s not unusual for someone to remember his or her blood type incorrectly or for there to have been an error somewhere during the testing and reporting process.

      Hope that helps.
      @MsGreene

      Added:
      • mimi la fleur

        I’m sure factions and dad and my mom We have re-test cliques doll but in the hospital told me that this is possible through a recessive trait

        Added:
        • Cheryl Greene

          Perhaps they know more in the hospital than I do. I’m happy to learn. If you have more information, please share.

          Added:
          • mimi la fleur

            I am not convinced by answering the hospital so I decided to resort to you and thank you for the answer, so I hope you answer yes or no, please

            Added:
  399. Nina

    Both of my parents have blood type O, while I as their daughter is blood type AB, Is it possible?

    Added:
  400. Lane Baxter

    My blood type is O positive, My husband is AB(he says it was on his dog tags in the military),one of our children is O positive. No hanky panky, no adoption. Is this possible or is he remembering wrong.

    Added:
    • Cheryl Greene

      He is likely remembering incorrectly or his blood test was recorded on his dog tags incorrectly, or the test was in error. This is easy enough to sort out with a round of blood tests for all three of you.

      Hope that helps,
      @MsGreene

      Added:
  401. John

    Both of my parents are type AB-, my brother and sister are both type AB-, I am type O+. I have discussed my issues with my mother and she refuses to even admit that either I was adopted or that there is even a possibility that I may have been switched at birth. Through research, I learned that another boy was born at the same hospital as I was and both parents are type O+. What do you suggest that I do?

    Added:
  402. Rachael

    My blood is O neg and one childish AB positive and one is AB neg so what’s the fathers blood type?

    Added:
  403. Leah Bridle

    What would the fathers blood group be??
    I have O positive blood group.
    Child 1 has O negative (male)
    Child 2 has A negative (male)
    Child 3 has O negative (female- twin 1)
    Child 4 has A negative (female -twin 2)

    I find it weird that child 1 has the same blood group as child 3, and child 2 has the same blood group as child 4. Both opposite sexes and child 3 & 4 are twins. What are the odds??

    Added:
    • Anonymous

      Father’s blood group could reflect as A(+/-) on the test results. And even though you have O positive, you likely have a hidden negative rhesus. To get a rhesus negative child, you will need (may be recessive) negative rhesus from both parents.

      Added:
  404. Christi

    My father is O+ my mother is O and I’m A + with my brother and sister but I have a sister from a other mother that is B+

    Added:
    • Christi

      My father is O+ my mother is O and I’m A + with my brother and sister could O make B+ babies

      Added:
    • Detra

      My father is O my mother is O I’m A could my father make B+ with some one else

      Added:
      • Cheryl Greene

        If one parent has type O blood and the other parent has type B blood, there is an 18.75% chance that each of their children will have type B blood.

        Hope that helps,
        @MsGreene
        Co-founder and Executive Producer, DrGreene.com

        Added:
  405. Omotola

    I am AS O+and my husband is AA O+ and we have a daughter that is AA O+ could u pls explain all possibilities becos my hubby is asking questions and I am certain she’s ours

    Added:
    • Cheryl Greene

      I am unclear on the question since you state that her blood type is the same as your husband’s. Can you explain his issues?

      Added:
  406. Hope

    My wife blood type is o plus and my blood is A plus and my new born baby Rh posative got juindce .please can you send how the treatment is good?.thank you.

    Added:
  407. Stacey

    my parents are both A positive and I am O positive is this possible

    Added:
    • Gary

      I’m the same, also as with both my parents, my brother is a pos, did you find out anything?? I think once the doubts in your head it’s hard to shake. Please let me know if you found out anything. Thanks

      Gary

      Scotland

      Added:
      • Lyn

        AO+ and AO+/- (commonly called A) can make an O+ Allele baby, because each parent has an O+ allele to pass down.

        Added:
    • lin ross

      My mothers bloodgroup was o negative,my father was o positive,all six of us children had opositive blood. .none of us had illness as children please explain.

      Added:
    • Susan

      Stacey, it is possible. You inherited your mother’s dna and your father’s. Simply put, you inherited the dominant or recessive blood type gene from each parent. Now given what we know are your parents dominant blood types, A, and your dominant blood type, O, we can deduce that your mother was A dominant and O recessive as well as your dads. So you then inherited the recessive O genes from mom and dad as your dominant blood type gene. My doctor explained this to my husband and I who are both B- and our second child, a daughter, was O- much to our surprise. Lol. This information is good to know! I had no doubt my husband fathered our daughter but I understood his questioning her blood type. I hope this helps and that I have explained it correctly.

      Added:
    • Cena

      Yes A positive plus A positive can equal an A or an o baby so don’t worry.

      Added:
  408. Paula Bennett

    I have A- blood and was told that when I was born in 1969 I had to have a blood transfusion to change it out because it was fighting against me. Can your blood type be changed like this? Both parents r positive

    Added:
  409. Rachel

    How can two parents being both be OO blood type and have a child with A positive?

    Added:
    • SUXAA

      VERY MUCH POSSIBLE . BECAUSE MY CHILD HAD 0+ DESPITE ME BEING A+ AND MY HUSBAND BEING A+ . AND IN SHA ALLAH NO CHEATING WAS DONE HERE :). IN YOUR CASE IT WORKED THE OTHER WAY ROUND

      Added:
    • Julia

      So sorry, need to retest to make sure results are accurate. O is recessive two O can only produce O children, to have O type you’re both OO so can only give an O to your children, according to modern science. Two A (comment below) are dominent each contributing the recessive allele O resulting in O child. As in AO and AO=OO

      Added:
  410. Swapnil

    Hi, we just had a our son. I’m B+ and my wife is B- but our son happens to be A+. Is this possible or hospital should we get his blood group rechecked?

    Added:
  411. Ali

    Hi, basically my dad has AB blood type and my mother has either 0 or A + but I’m a A- is that possible??

    Added:
    • Cheryl Greene

      There are several variables in your scenario making it very difficult to determine if this is a possible combination or not. But this information may be helpful:

      If one parent is AB+ and the child is A- the other parent could be A+, B+, AB+ or O+.
      If one parent is AB- and the child is A- the other parent could be A-, B-, AB- or O-.

      Best,
      @MsGreene

      Added:
    • Eric

      Hi. My father lives in spain he wanted me to come live with him there. During the process of the paper work, a DNA test had to be done to prove if truely am the real son of my father which they took some tissues from my mouth . just yesterday the results came out and my DNA matched totally different from my father’s. I had a talk with my mom to know whether she had an affair with another man whiles she was with my father. She was clear to me that such thing never happened and I believed she was telling me the truth. I also believe my father is my real father because, there are a lot of resemblance between me and my father’s mother that is my grandmother but the DNA test proves the man I believe is my father is not. Please can there be any possibility that such thing can happen. I really need a quick reply because we have only one month to appeal to the Spanish embassy.

      Added:
      • hassan

        Me & my wife is o+ but our son is a+ does it means my wife cheated on me please tell me posobilty

        Added:
        • Cheryl Greene

          Hassan,

          If the types do not seem possible, consider that there could be an error in one of the three blood type tests. It is not unheard of for one of the three tests to be incorrect, reported incorrectly, or remembered differently than reported.

          The best way to determine paternity is by DNA paternity testing.

          Best,
          @MsGreene

          Added:
          • hassan

            Please inform me whether it is possible that two o can produce A or B blood type baby? Where modern science says not possible. Please

            Added:
          • Cheryl Greene

            Dear Hassan,

            As you say, modern science says it is not possible for two parents with type O blood to have a child who is either type A or type B. It is possible for one of the three people to have incorrect test results (testing error), have the results recorded or reported incorrectly, or have one of the people remember the results differently than he or she was told.

            As Dr. Greene says, “These are general rules, though, and exceptions apply. Very rarely, gene mutations may change the rules such that “impossible children” become possible.”

            If you are concerned about your child, is it relatively easy to have DNA paternity testing done. This checks both the father and child’s DNA to look for specific markers and is much more detailed than blood type testing.

            I hope this is helpful.

            Best,
            @MsGreene

            Added:
  412. Kathryn c

    My mother is rh negative, my father is O positive. I am type O positive. She had no pregnancy issues with 3 of her children however, her 4th child required transfusions and ended up with severe cerebral palsey. How did the 3 not cause any pregnancy problems?

    Added:
  413. laila

    My father is O and my mom is A or B and i am AB is that possible?

    Added:
    • Mom

      Yes Laila….it is. My child is AB. Her father is O and I am B. Her maternal grandfather is AB and her paternal great-grandfather is A. There is NO DOUBT of her paternity. Recessive genes do factor in and A and B are dominate. The chart is wrong in our case too.

      Added:
      • Jenna

        I think you might be mistaken. I had a the same situation and DNA test proved that the man was not my father. The DR stated that is not possible. In the comment above look at the chart it is not possible

        Added:
      • Julia

        Wow, anger at others does not change science. In 30 years of medicine I have never seen a verified case you describe (mom). All issues were resolved one of two ways, either a bad test result or different paternity/maternity.

        Added:
    • Jenna

      No it’s not possible

      Added:
  414. Roch

    I am B+ and my mother is O-, so what blood type does my father have to be?

    Added:
    • Steven

      Hi My son has a blood group of O+, My blood group is B+ & my wife has A+. with our Blood group is it possible to have our kids with O+ blood group? I would really apprecite your feedback. Thanks.

      Added:
  415. Missy

    I just found out my dad is o negative and that my mom is b positive. I am ab positive. If I recall genetics correctly my dad cannot truly be my dad. I know that his and my blood types are correct. Can you please confirm or correct my thinking ? Thank you

    Added:
      • Missy

        My dad just had heart surgery and is o negative. I was also retested and am ab positive.

        Added:
        • Cheryl Greene

          There are rare mutations. There are things we don’t know about science. And above all else, I’m not an expert (I’m not a doctor, but I am interested in this topic). That said, you may want to have an honest talk with your mom.

          @MsGreene
          Co-founder and executive producer, DrGreene.com

          Added:
          • Mom

            If you are NOT a Doctor and only interested in this topic, then WHY are you answering as if you are??? My child is AB. Her father is O and I am B. Her maternal grandfather is AB and her paternal great-grandfather is A. There is NO DOUBT of her paternity. Recessive genes do factor in and A and B are dominate. The chart is wrong in our case too.

            Added:
  416. Holly

    My mums blood group is O and mines A+ so what would that make my dad ?

    Added:
  417. FH

    Hi,I am A-,but both my parents are A+.Is it possible?Thanks

    Added:
    • Cheryl Greene

      Yes. If both parents are blood type A+, each of their children have a 93.75% chance of being blood group A and a 6.25% chance of being Rh-.

      Hope that helps.
      @MsGreene

      Added:
  418. deedea

    sorry it me can some one tell me what this mean im a daughter with a+ my borther a+ my dad a+ my mother rh …how this go

    Added:
    • Cheryl Greene

      Let me see if I can help figure this out.
      You are A+
      Your brother is A+
      Your father is A+
      Your mother is ?

      Are you asking what your mother’s blood type could be?

      Sorry, but I’m having trouble figuring out what your question is.

      Added:
      • deedea

        yes my mother rh my dad not rh his a+ .. i sill haveing trouble to.

        Added:
        • Cheryl Greene

          Hi Deedea,

          Genetics can be confusing! Because blood tests are common many people have questions about the genetic information found in the ABO blood group and Rh system. Blood types are A, B, AB and O. Rh is listed as – or +. This means people can be A+, A-, B+, B-, AB+, AB-, O+ or O-.

          Please read Blood Types 101 and the RH System for an explanation.

          I hope that helps,
          @MsGreene

          Added:
          • deedea

            ok thank you but i sill dont know why my mother say to me we dont have the some boold type

            Added:
          • Cheryl Greene

            I’m not sure what she is basing that on, since I don’t know her blood type (A, B, AB, or O). I’m also not sure what the issue is or what your concerns are, but children don’t necessarily have the same blood type as their parents. Does that help?

            Added:
  419. Joann

    Both of my parents had type O blood, I am A+. Is this possible?

    Added:
  420. iskandar

    Both my parents have type blood O. Why is it I am a type B? Is this possible?

    Added:
  421. Patrick

    My father was O positive and my mother is O negative. I am A negative. How is that possible?

    Added:
    • Kitty

      It is not…. Sorry, Patrick.

      Someone had to have an A to contribute. Unless you are one of those extraordinary mutations/exceptions. If you are not, I would make certain to retest your blood type, or have a serious heart to heart with your mother.

      Added:
      • Mom

        The more answers I read from you the more angry I am getting!!! Yes it is possible! You yourself are saying “unless you one of those extraordinary mutations”….maybe they are! People keep telling you their parents are O and they are something else. You think everyone of these mothers cheated on their husbands??? Shame on you for answering when you have NO WAY of knowing for sure! Recessive genes have to factor in when A and B are dominate over O. Stop destroying lives!!!!!

        Added:
        • T

          Thankyou for saying that. I totally agree.

          Added:
        • Anonymous

          I’m O+ and hubby is A+ but our child is B+. Hospital says it can happen but hubby thinks I was cheating. Which I did not!

          Added:
        • tiddly

          I read one of your explanation

          “My child is AB. Her father is O and I am B. Her maternal grandfather is AB and her paternal great-grandfather is A. There is NO DOUBT of her paternity. ”

          Your husband cannot, in anyway, be O because an AB child cannot come from an O that is not how genetics work. He might actually be an AO or AB and might have mistaken his blood type because O is a very common blood type despite it being a recessive gene. This is not a simple chart saying this, but scientific proof that have been examined thoroughly from plants to animals, including thousands of people. The chance of this happening would usually come from blood transfusions or organ transplants which will change back to the original blood over time, unless it is bone marrow.

          I think a lot of people’s parents don’t know their blood types and just chose the most common one.

          Added:
          • Cheryl Greene

            RE: “I think a lot of people’s parents don’t know their blood types and just chose the most common one.” I completely agree. In addition, I believe blood types are sometimes incorrect (whether that is a lab error or a reporting error) or remembered incorrectly.

            If paternity is the issue, doing DNA paternity testing is in order, not relying on blood typing.

            Added:
          • Julia

            Amen! Anger over science facts do not change the facts. All answers advocate retesting and having an open communication with parents. There are hundreds of thousands to millions of adoptions, grandparents raising grandchildren as their own, illigitamate births And yes, births resulting from adultery. If truth makes you so angry then this is not the forum for you. This is America and we all have a voice.

            Added:
  422. naresh nayak

    My wife and I both have o positive
    blood type. Is it possible let for our
    chilease to be b positive?

    Added:
  423. Nikki

    My mom is positive O while my father is O, why do I have an A blood type?

    Added:
  424. Jdbek

    My wife and I both have A positive blood type. Is it possible let for our chilease to be A negative?

    Added:
    • Jdbek

      Possible for our child

      Added:
      • Melissa

        Yes. It can skip a generation so I’m willing to bet someone, either one of your parents or her parents have an Rh negative type.

        Added:
  425. Duckie

    My parents share the same blood type which is O. My brother and I fall under the same type, except my younger sister who is a B. Is she my parent’s daughter? I did some research but your in depth answer would be much appreciated.

    Added:
  426. deedea

    can some one tell me what this mean .my morther rh my dad a+ my borther a+ sister a+

    Added:
    • Cheryl Greene

      There is not enough information in your question to be able to interpret, but it is possible for both parents to be Rh+ and have children who are either Rh+ or Rh-. Does that help?

      Added:
      • deedea

        my mother rh dad a+ what it mean/

        Added:
        • Cheryl Greene

          What is your mother’s full blood type?

          Added:
  427. David Rae

    My partner has blood type 0+ and my daughter has rhesus negative…what would the fathers blood group have to be?

    Added:
    • Cheryl Greene

      Here is some information that may be helpful to you. For more details see: Blood Types 101: An Introduction to ABO Blood Types and the Rh System.

      “… The Rh system is actually far more complex than the ABO system in that there are 35 different possibilities that one could inherit from each parent. These, however, are roughly grouped into positive and negative types. In this system the positive are dominant over the negative. Thus if your genetic type is ++ or +-, your blood type will be Rh positive. Only if your genetic type is – – will you be Rh negative. This means that if both parents have Rh+ blood with the +- genes, they could have children who are ++, +-, or – -. In other words, their children could be either Rh positive or Rh negative. Children who are Rh negative can have parents who are either Rh positive or Rh negative.

      This is why two parents who have O positive blood could easily have a child who is O negative. In fact, most children who are O negative have parents who are positive, since the +- combination is so much more common than the – – combination.”

      I hope that is helpful.
      @MsGreene

      Added:
  428. Terri

    My mother has passed but was RH-. My father is O+. My brother is O- and I am O+. Are we full siblings?

    Added:
    • Cheryl Greene

      It’s impossible to know from the information that you’ve provided whether or not you are full sibling. But, from this information there’s no reason to doubt that you are full siblings either.

      If one parent it Rh+ and one is Rh-, each of their children has a 75% chance of being Rh+ and a 25% chance of being Rh-.

      For a detailed explanation see Dr. Greene’s Q&A: Blood Types 101: An Introduction to ABO Blood Types and the Rh System.

      Best,
      @MsGreene

      Added:
  429. Lisa

    Both parents are O+, my two siblings are O+ however, I am A+. Is this possible? I read somewhere that a mutation can happen. Is this true?

    Added:
  430. ruebin

    Can a A positive father and an o neg mother make an a neg baby??

    Added:
  431. Jonnie

    I have a twin sister her blood type is B my mother is B my father is O, I am AB negative. I know that it’s possible for twins to be fathered by two different men if conceived within 72 hours of each other. My sister swears that her and I have different fathers. Is that possible. (we are fraternal twins)

    Added:
    • Anna

      I am no expert but it is plausible that you and your twin sister have different fathers. Parents with B and O cannot conceive a child of AB blood type, unless you are one of those rare mutations. However it is plausible that a B combined with an O blood type would produce a daughter with B blood type. Therefore it is possible that you may have separate fathers, but before jumping to conclusions I would suggest everyone has their blood type retested and you have a conversation with your mother. Hope this helped.

      Added:
  432. A

    I give blood and they told me my blood type is A negative.My mom is A positive and my Dad is O positive.All my grandparents are also positive.My dad wants a DNA test but I keep telling him it is possible?How can I explain it to him?

    Added:
    • Cheryl Greene

      Here is Dr. Greene’s explanation:

      Rh System
      Another medically important blood type is described in the Rh system. These genes were first discovered in the rhesus monkey, hence the designation Rh. The Rh system is actually far more complex than the ABO system in that there are 35 different possibilities that one could inherit from each parent. These, however, are roughly grouped into positive and negative types. In this system the positive are dominant over the negative. Thus if your genetic type is ++ or +-, your blood type will be Rh positive. Only if your genetic type is — will you be Rh negative. This means that if both parents have Rh+ blood with the +- genes, they could have children who are ++, +-, or –. In other words, their children could be either Rh positive or Rh negative. Children who are Rh negative can have parents who are either Rh positive or Rh negative.

      This is why two parents who have O positive blood could easily have a child who is O negative. In fact, most children who are O negative have parents who are positive, since the +- combination is so much more common than the — combination.

      I hope that helps!

      Added:
    • deedea

      hi my mom D dad A x brother A x me A what this mean do you know

      Added:
  433. Stacy

    My blood type is A + (My mothers is A+), My husband blood type is B+ (His mother’s blood type is AB+). I have a son who is 0 + and a son that is A-. Is this possible?

    Added:
    • omar

      yes, it is possible. you may have the genotype AO and your husband have the genotype BO, so AO . BO You and your husband have passed down your “recessive” gene “O” to your son, then son would receive the genotype “OO” which is blood type O. Your second son took your dominant gene “A” that is blood type “A”, his negative Rh came from both of you, you and your husband could have the genotype “Dd”, then your second son received the recessive gene “d” from mom and dad and turned out to have acquired the Rh genotype “dd” which is Rh (-) ve.
      hope that of help you.

      Added:
  434. Jules

    I never really put too much thought into this until I had my daughter…where do I begin. I remember about a decade ago, my older brother mentioned his blood type was AB( at this time I can’t recall if it was + or -). I didn’t even know what my blood type was until a few years after this, when I had my daughter. I am O+ as well as my daughter is. While I was pregnant with my daughter, I ran into health problems and became a patient of a couple specialists beyond my PCP who inquired about family history to try to have some information to go on. Upon asking my father, I wound up getting no answers. I had asked on numerous occasions for any information. The response I received was “Stop by sometime and we’ll sit down and go over anything.” I did. Four times while I was pregnant. That was literally the ONLY sentence I could get out of him. I wound up having to tell the doctors I was adopted and had no clue what my families medical history was and had my daughter three months early. My parents are now divorced and due to personal reasons, I chose to have nothing more to do with them. Growing up, my mother did have a tendency of well, ‘getting around.’ I guess what I wondering is, is there anyway or any tests that could determine if the person listed as the father on my own birth certificate is in fact my biological father or not without his cooperation? Knowing anything would be nice.

    Added:
    • Mrarchery

      No.

      Added:
  435. Aley

    So if both of my parents have B+ blood is it possible for me to have O+ or is there a scandal here?

    Added:
    • Anna

      It is possible as they could both be BO + which is capable of producing BB+, BO+ OR OO+

      Added:
  436. Kristie

    My husband and I were told when our daughter was born almost 27 years ago that she had A+ blood the same as my husband and I. She has had two children and has always been told she was A+. During her blood work for her second pregnancy it came back O+. I said it can’t be were have your delivery card that says A+. The hospital ran the test again and again it came back O+. How can this be?

    Added:
  437. Diana

    If I am A+ an my father is B+ an my mother is O- is this possible.

    Added:
    • Cheryl Greene

      The scenario you outlined is not a possible outcome, but before you jump to any conclusions, it would be wise to re-test all three parties. It’s not uncommon for one or more of the tests to be inaccurate or to be reported inaccurately or remembered differently than reported.

      Added:
      • Diana

        No I was tested in the army. Thank you

        Added:
        • Cheryl Greene

          Still wise to have all three parties re-tested before jumping to any conclusions.

          Added:
    • omar

      genetics has always something to say!! if three of you are confirmed with “forward and reverse typing” using a sample of your blood as you mentioned in your query! then i would advise you to go for genetic testing, you and your parents. you don’t know!! all scenarios are possible; mutation, chimera…etc. or one of you might be “phenotypically” typed “A,B, or AB”, but “genetically” your blood type is different from what appear to be in your blood test!! genetic test would reveal the “unknown”. even though, your scenario above seems to be not possible, but with genetic test is POSSIBLE! go for it. no worry.
      hope it is of help to you.

      Added:
  438. Yaliet hernandez

    My mom blood type is A+ my dad is O+ it’s possible that’s I am AB- ?

    Added:
    • Cheryl Greene

      While this is not considered a possible outcome, it’s not uncommon for one of the three test results to be remembered incorrectly, or recorded incorrectly or even possible that the test results are not correct. Other explanations include a sperm donor. Before you jump to conclusions, it’s wise to ask non-threatening questions that include requesting re-testing of blood types.

      @MsGreene (not MD)
      Executive Producer, DrGreene.com

      Added:
    • omar

      excluding lab “error”!!! that is “possible”!! we are testing in the lab for (proteins)/Antigens that stick to the surface of your red blood cells. we are NOT testing for “genes”!! you or you parents could have blood typed “phenotypically” as “A”, “O”, or “AB”, but “genetically” you could have different blood type!! yes, that is possible. you and your parents advised to go for genetic test to clarify this (unexpected) outcomes.
      hope it helps. thank you.

      Added:
    • Patricia

      Hi my parents are deceased and my mom.I believe me was A positive and my dad well not sure if he was my real dad my mom never had blood test he was O- and I’m A positive. Anything you could tell me from that? Or anything else i can look into feel stuck and have always been confused he was Italian and my mom french and italian.thank you

      Added:
  439. shivani

    if mother has AB blood group and father has O blood group is it possible baby will have AB blood group?
    if it is possible then how?

    Added:
    • Beth

      No it is not possible as the child will get one gene from its mother and one from its father the child would either have AO (A) or BO (B) blood type

      Added:
    • omar

      yes it is possible! through “mutation”, this one scenario. the second scenario is, your father could be a Bombay” blood type! the third scenario is, your mother could be of a rare cis-AB type!! in the later scenario” mother is of genotype AB/O father is O/O. MOM passes down the whole gene “AB” as she is “cis” and DAD passes down his “O” gene, the product would be “AB/O” which is cis-AB and that is how you appeared to be as blood type “AB”.
      is it of help to you?

      Added:
  440. Tina

    Hi, I wonder if you can help me, my blood group is B positive and my husband is O positive, my child was born as B negative with Anti C. The Anti C has gone from her blood now, but mine is now B positive with anti C. Please can you tell me how my child has negative blood when my husband and I are both positive and what anti C is.
    Thank you

    Added:
    • Beth

      As positive is a dominant gene you only need one copy for that trait to show. So whilst you have positive blood you could have either +- or ++ given your child is negative it is most likely that both you and your husband have +- your child receives one gene from each parent so they may have received negative from both of you resulting in their blood being negative.

      Added:
  441. Teodora

    Hello,

    And thank you for the article! I was wondering, as I am AB +, my Mom is B +, and my Dad is O +, what is the possibility that my Dad is not my biological father? Thank you in advance!

    Added:
    • Cheryl Greene

      There are a few options:
      — One of the three of you isn’t the blood type you think you are. This is pretty common.
      — There was a rare genetic mutation.
      — He’s not your father.

      The first step is to discuss this with your parents. They may be able to solve the mystery. Next you could have all three of your blood types retested. Finally, you could have DNA paternity testing done to resolve any questions.

      Hope that helps,
      @MsGreene

      Added:
      • BN

        Hello Teodora,

        If the blood groups that you have mentioned are correct – then clearly they aren’t your parents.

        Cheers!

        Added:
    • Mom

      Teodora…I say yes! My daughter is AB. I am B. Her father is O. There is NO DOUBT of her paternity. Her maternal grandfather is AB and her paternal grandfather is A. Recessive genes have to play a part in this and A and B are dominate. The charts are wrong in our case too.

      Added:
      • Jenna

        You keep repeating the same thing over and over, no one that knows how the blood types work is believing it. Go get tested and show the results. I had two different DNA centres conduct the same test with the same blood types you speak off and both centres stated the same thing there is no possible way. Oh and the results came back that he was not my father.

        Added:
        • Gill

          My mother is 0- i am ab+, we have both been genetically tested and blood types reconfirmed by two different labs and they match our nhs blood typing……and guess what she is my mother and she still has o- and i am still ab+

          So seen as you know all about the blood types and their possibilities explain that. Or are you now going to tell me that its still impossible or wrong?

          Please feel free to get in touch and review all my paperwork but until then i think you should get off your soapbox and accept that just because you didnt get this outcone others cant

          Added:
          • Cheryl Greene

            Gill,

            This is all very tricky. As Dr. Greene says above, “While there are rare exceptions, the following information on blood types applies to most people.”

            Additionally, while we know a lot about genetics, science is constantly uncovering what we don’t know. Perhaps there are subsets of type or undiscovered types that are yet to be discovered that will explain situations that we think are impossible now, but are in fact merely rare.

            Best,
            @MsGreene

            Added:
  442. theresa

    Hi I’m O+ but my sister say they are A+. Can that happen?

    Added:
    • Cheryl Greene

      If one parent has type O blood and the other has type A blood, then their children could be O or A.

      Added:
  443. Wendy

    If one grand parent has type O positive blood type, and one has AB negitive, and heir child is AB negitive, can the grandchild have o positive blood type?

    Added:
    • Cheryl Greene

      I think I understand your question, but to clarify — one of your parents has AB- blood and you have O+ blood. You’re wondering if there’s any way the parent with AB- blood could pass along O+ blood type because one of his or her parents was O+. Is that correct?

      If one parent is AB, no matter what the other parent’s blood type, the child can only be A, B, or AB. That said, there are rare genetic mutations in blood types and rather common mis-reported blood types. This can be because the test is in error, someone in the chain reported it incorrectly, or someone is remembering it differently than it was reported.

      DNA tests are the best way to determine paternity (and maternity), but simple re-testing of both parents and the child is the best place to start.

      I hope that’s helpful.
      @MsGreene

      Added:
  444. Abigail

    Hi! My husband and I are both O+ our daughter born on Oct 4 2015 is A+ how can that be possible?

    Added:
    • Cheryl Greene

      There are very rare genetic blood type mutations that would result in this combination. More likely one of the three of you are not the blood type that you think you are. This can happen because one of the tests is in error, someone in the chain reported the incorrect blood type, or one of you is remembering it incorrectly.

      It’s probably smart to have all three of you retested.

      Added:
  445. Ayesha

    Everyone in my family is A+, like my parents, my sister, uncle, aunty, cousins, grandmother, almost everyone with my grandfather only the exception. He is O+. I do not know my blood group, what could it be?

    Added:
    • Ayesha

      Both my parents are A+. My mom’s parents are A+ and O+ and her 2 brothers are also A+. My dad is also A+ positive but I do not know my grandparents’ blood type. My dad’s siblings are all A+. What could be my blood type?????

      Added:
      • Cheryl Greene

        Two parents with A+ blood can have children with A or O, Rh+ or Rh- blood types.

        For a full eplanation see Dr. Greene’s article Blood Types 102.

        Added:
        • Ayesha

          I did a blood type test and found that I am A+.

          Added:
          • Cheryl Greene

            Thanks for letting us know the results. This field is endlessly fascinating.

            Added:
  446. Sonia

    I am A positive and hubby is B positive but our child is O negative. Is that possible?

    Added:
    • Cheryl Greene

      If one parent is A positive and one parent is B positive their children could be A, B, AB, or O and positive or negative. O negative is the least likely outcome, but it is possible. For a complete explanation see Dr. Greene’s article Blood Types 102.

      Added:
    • Jackie

      Yes that is very possible an A gene and B gene can have an O child. And both parents being rh+ can have a rh- baby. Hope this helps

      Added:
    • veron fregellana

      my mother is type o and my father is type ab.. is it possible that none of them match my bloodtype?

      Added:
      • veron fregellana

        my mother’s bloodtype is o and my father’s bloodtype is ab. my bloodtype is b, is it possible that none of them match my bloodtype?

        Added:
        • Cheryl Greene

          If one parent has O type blood and the other has AB, their children can only be type A or B.

          For a full explanation, see Dr. Greene’s Q&A Blood Types 102.

          Best,
          @MsGreene

          Added:
  447. Alex To

    I am O+ and my wife is A+ with a child of O-. could such be possible. I need full clarification. Thanks.

    Added:
    • Cheryl Greene

      It is possible for one parent to be O+ the other A+ and their child to be O-. I know, it sounds odd, but there is a 25% chance their child will be type O and a 6.35% chance the child will have Rh- blood. For a full explanation see Dr. Greene’s article: Blood Types 102.

      Added:
      • unknown

        Is it possible to have have mother A+ and father O+ =O+ kid?

        Added:
        • Cheryl Greene

          If one parent has A+ and one parent and O+ blood type there is a 25% chance that each child will have type O blood and a 75% chance that each child will have type A blood. For a details explanation see Dr. Greene’s Q&A Blood Type 102.

          Added:
  448. Nikki

    My parents are both O- and my brother is O+ and I just donated my blood and asked for my blood type. They tested a sample of it and said it was most likely B+. Uhm, are they not my parents?! What’s going on?!

    Added:
    • Nikki

      I was their first child if that makes a difference. People say I look exactly like my mom, so they have to be my parents?!

      Added:
    • Cheryl Greene

      Two O- parents can only have O- children, with very rare exceptions of gene mutation.

      There are several explanations — perhaps both parents aren’t O-, one or more of the past blood type tests were in error, one or more of the blood type tests were reported incorrectly, one or more of the parties recorded or are remembering their blood type incorrectly.

      Would your parents be open to a discussion? You could say that you’ve done some research and you think their blood types may be in error. Would they mind being retested? If they are wrong, it would be helpful for them to know in case they ever needed a blood transfusion. If they have something to share with you, this would give them an opportunity to do so.

      Added:
      • Nikki

        Hey so I got my accurate blood result mailed in. I turned out to be O+ instead of their guess of B+ (phew at least the letter is right). And my parents keep insisting they’re both O- and I tell them one of them HAS to be O+ but yes, I will definitely get both of them retested.

        Added:
  449. Laura

    I am AB-, my ex-husband is A+. Our children are O+ and AB+. Is that feasible given the types of my ex and me?

    Added:
    • Cheryl Greene

      If one parent has AB- blood and the other has A+ blood, their children can have A, B, or AB blood types and + or -. O+ is not a possible outcome unless there is a very rare genetic mutation.

      If you are concerned, consider having blood types retested or a paternity test.

      Added:
  450. Mike

    I asked a 2 part question, the 2nd question was answered I hope you can answer the 1st one.
    I’m the father of 3 adult children & my blood type is O-, my wife and 3 children have the same blood type B+. I’ve attempted to get answers on my own at differint web site’s but it’s to difficult to understand. From what I understand that could not be the case.

    Added:
    • Cheryl Greene

      Yes, that’s possible. The odds for blood types are for each child and are averaged over large sample sizes. Here’s an example – if a mother was B+ and a father was O- each of their children would have a 75% chance of being type B and a 75% chance of being +. That doesn’t mean that if the couple had four children one would be type O-.

      The odds are reset with each child. These odds only average out in a large data set. An example of this is if you toss a coin there is a 50/50 chance that you will get heads. If you get heads the first time, the second time you are not more likely to get tails. But if you toss it 100 times you are likely to have half heads and half tails. Does that make sense?

      Added:
  451. Joseph Betchel

    One parent AB POS,the other Bpos. The child Oneg?All blood types cofirmed.Is this possible??

    Added:
    • Cheryl Greene

      This is not a combination that is considered possible. As Dr. Greene points out in his post Blood Types 102 “These are general rules, though, and exceptions apply. Very rarely, gene mutations may change the rules such that “impossible children” become possible. Today there are over 600 blood types known (as well as other tissue types called HLA types), which can make paternity testing far more accurate — but still not perfect.”

      Added:
  452. Mike

    I’m the father of 3 children, 1 boy & 2 girls, all my children have the same blood type as my wife, is that possible?

    Also I enlisted into the United States Army in 1979, when I enlisted I was told that I was 0+, and that’s what they put on my dog tags. Years later before going overseas during Desart Storm I was told I was 0-, why was that.

    Added:
    • Cheryl Greene

      Likely one of your tests was in error, recorded incorrectly, or you are remembering it differently than was reported. This is not at all uncommon.

      Added:
  453. Kay

    I have A- blood. My son has O- blood. His teacher said it is impossible for him to be my child. Is this correct?

    Added:
    • Cheryl Greene

      That is not correct. If one parent has A- blood and the child has O- blood, the other parent could have either A- or B- or O- blood.

      Added:
  454. Kate

    I am pregnant for the first time and just found out I am ab-. My mother is sure she is a +, and my dad who is recently deceased belived he was a b+, but could also be b-. I e read the both parents need to be negative to produced an ab- child. Is this an impossible situation?

    Added:
    • Cheryl Greene

      It is possible for an A+ parent and a B+ parent to have an AB- child. For a full explanation, read Blood Types 102 by Dr. Greene.

      Added:
  455. Confused

    My mom is O+ Dad is AB+. I am A(RhNeg) All 7 of my siblings have positive blood types. I have 4 kids all of which are all Positive. My question is: Is it possible that My parents are both my biological parents? Is saying “I have RH Negative blood the same as saying just Negative blood type?

    Added:
    • Cheryl Greene

      Rh- does mean the same thing as Negative or -.

      It is possible for an O+ parent and an AB+ parent to have an A- child.

      For more details see Dr. Greene’s Q&As Blood Types 101 and Blood Types 102.

      Added:
    • D.latha

      Hi Dr Greene,
      My blood group is o+
      My husband group is b+
      My daughter o+
      My son what is the blood group?

      Added:
      • Cheryl Greene

        If one parent is O+ and the other is B+, each of their children will have a 75% chance of having type B blood and a 25% chance of having type O blood. Each child will hae a 93.75% chance of being Rh+ and a 6.25% chance of being Rh-.

        Hope that helps,
        @MsGreene
        Executive Producer, DrGreene.com

        Added:
  456. Carla

    I recently found out my brother & I were adopted. He is B positive & I am O positive. Can we be biological brother & sister or have 1 common biological parent?

    Added:
    • Cheryl Greene

      If one parent is B+ and one parent is O+ their children could be either B or O, + or -.

      Added:
  457. Tina

    Hello. My mother (deceased) was type 0-. My father is type B+. There are 4 siblings. The first two are my brother and myself who are A+. The other two are twins with 0+. I have read over and over that my brother and I don’t have the correct blood type from the combo of our parents. Could there be another explanation besides us having a different father… something rare that can occur . All four of us look very similar to each other. I have read that there are instances when someone with A can be mistyped as an 0. Thanks!

    Added:
    • Cheryl Greene

      There are a few possible explanations — one or more of the blood types could have been recorded in error, the test could have been false, or someone’s memory of his or her blood type could be wrong. In addition, as Dr. Greene points out in his Q&A Blood Types 102 “These are general rules, though, and exceptions apply. Very rarely, gene mutations may change the rules such that “impossible children” become possible. …
      Today there are over 600 blood types known (as well as other tissue types called HLA types), which can make paternity testing far more accurate — but still not perfect.”

      I hope that’s helpful.
      Cheryl

      Added:
  458. Julie

    I am AB negative. My parents are deceased, but would they both have needed to be AB negative? Thanks for the info!

    Added:
    • Cheryl Greene

      Since each parent contributes one gene, your parents could have been A & B, AB & A, AB & B. Make sense?

      Added:
      • Julie

        Thanks for the reply! Regarding Rh+ and Rh-, isn’t it more likely that they are both Rh-?
        I found out today that my dad was A negative.

        Added:
  459. michelle

    My father is A+ my mother is O+
    All my siblings are O+ only I am the one with A+ . Is it possible ? I mean all my siblings are O+ ..so even mine should be O+ right ?!

    Added:
    • Cheryl Greene

      If one parent has O+ and one parent and A+ blood type there is a 75% chance that each child will have type A blood and a 25% chance that each child will have type O blood. For a details explanation see Dr. Greene’s Q&A Blood Type 102.

      Added:
  460. Matthew

    My Mom is B+ and my Dad is O-. My blood is AB+. Is that possible or should I be suspicious of the milkman?

    Added:
    • Cheryl Greene

      While this is not considered a possible outcome, keep in mind there may other reasons than the milkman. It’s not uncommon for one of the three test results to be remembered incorrectly, or recorded incorrectly or even possible that the test results are not correct. Other explanations include a sperm donor (not of the milkman variety). Before you jump to conclusions, it’s wise to ask non-threatening questions.

      Cheryl Greene (not MD)
      Executive Producer, DrGreene.com

      Added:
  461. nikkigab

    I’m confused. Please help. I am b- husband is ab+ we have one son that is O negative and a newborn that is B positive. Per your research the O Negative child is not his how can that be? I think my husband may not know his blood type.

    Added:
    • Cheryl Greene

      It is not uncommon for people to remember their blood type incorrectly. In addition, a blood type test can be inaccurate or even mixed up in the lab with another sample. It would be smart to have the two of you and the two children retested if you are interested in sorting this one out.

      Added:
  462. rishi

    when blood group of male is A and female is B then new generation is ?

    Added:
    • Cheryl Greene

      In this combination, the child could be A, B, AB or O. For a full explanation see Blood Types 102 by Dr. Greene.

      Added:
  463. Carrie

    I am trying to figure this out.
    I am O- my youngest sister just found out she is AB-
    My mom has told me that she is an O as i have questioned my bio father. but with reasearch i see it is not possible for an O to have a AB child. I know for a fact my sister is my mothers and fathers do to medical stuff she has gone through. so i am assuming my mom has lied to me about her blood type to get me to drop it?!?!

    Question is I am correct right??

    Added:
    • Cheryl Greene

      The scenario you’ve outlined is correct, however, there are rare genetic mutations that can result in blood types that we don’t expect. As Dr. Greene points out in Blood Types 102 “These are general rules, though, and exceptions apply. Very rarely, gene mutations may change the rules such that “impossible children” become possible. The geneticists at Stanford wrote a great explanation to this on the website for The Tech Museum of Innovation.

      Today there are over 600 blood types known (as well as other tissue types called HLA types), which can make paternity testing far more accurate — but still not perfect.”

      Added:
  464. Tracy Berry

    My mother was o+ and my dad was o- my blood type is A- with RH. My dads mom was AB- with RH. so from what I read from the last comment my dad probably wasn’t my biological father is that right?

    Added:
    • Cheryl Greene

      An O+ parent and an O- parent can’t have an AB- child, however, there are rare genetic mutations that can result in blood types that we don’t expect.

      As Dr. Greene points out in Blood Types 102 “These are general rules, though, and exceptions apply. Very rarely, gene mutations may change the rules such that “impossible children” become possible. The geneticists at Stanford wrote a great explanation to this on the website for The Tech Museum of Innovation.

      Today there are over 600 blood types known (as well as other tissue types called HLA types), which can make paternity testing far more accurate — but still not perfect.”

      Added:
  465. Tia Night Eagle

    Hello,
    My Father is O positive and my Mother A negative… I am A negative and my sister is B negative my brother is B positive,,,,,, so I’m confused,, are we full siblings?
    Thank you for your time,
    Tia Night Eagle

    Added:
    • Cheryl Greene

      If one parent is O+ and the other parent is A-, their children can be type A or O, + or -.

      For a full explanation see Dr. Greene’s Q&A Blood Type 102.

      As Dr. Greene says in that article, “These are general rules, though, and exceptions apply. Very rarely, gene mutations may change the rules such that “impossible children” become possible.”

      If you are concerned, DNA testing is the best way to clear things up.

      Added:
  466. Cate

    I’m one of 8 children born to the same parents. Both parents are O+. I’m the only child out of the 8 with O- blood group. I have 4 children to my ex husband who is O+ and 2 of them are O+, 2 are O-.

    It seems very odd to me that out of 8 I’m the only one but out of 4 we got 50/50!

    I also have some illnesses that are inherited and I’ve passed to one of my granddaughters. Is it possible my father isn’t my father?

    Added:
    • Cheryl Greene

      Odds are a strange thing. With two O+ parents each child has a 6.35% chance of having O- blood. That means out of 10,000 children born to two O+ parents 625 of them should have O- blood. But each child is either + or -. It’s like rolling dice. You should get a 6 once out of every six rolls, and yet you don’t. You may get three in a row and not get another the next 100 times you roll. If you roll long enough (unless the dice are loaded) it will average out to 1 in 6 rolls.

      Does that make sense?

      Added:
  467. Mishal

    my parent’s blood group is o+ve but mine is B+ve is there any chance for this type?

    Added:
    • Cheryl Greene

      Two O+ parents can only have children who are O+ or O-. However, as Dr. Greene points out in his Q&A Blood Types 102, “These are general rules, though, and exceptions apply. Very rarely, gene mutations may change the rules such that “impossible children” become possible.”

      Added:
  468. Candace brooks

    Hello…
    I just had a baby she is B negative and I am O positive I was just wondering what blood type would her father have to have? Really freaking out. Can you inherit blood type from down the line?

    Added:
    • Cheryl Greene

      In this scenario, the father would be B+ or AB+. For a full explanation go to Dr. Greene’s Q&A, Blood Types 102.

      Hope that helps!

      Added:
    • Candace Brooks

      Hi, me again. Is there possible that babies can inherit a blood type from down the line?

      Added:
      • Cheryl Greene

        I don’t know what you mean “from down the line”. Do you mean from a previous generation? Such as a grandparent?

        Added:
        • Candace Brooks

          Yes.

          Added:
          • Cheryl Greene

            We all are impacted by our ancestors. In blood types, we get one gene from our father and one from our mother. It is possible in that way for a gene to pass “silently” from a grandparent to a parent, to a grandchild — but that is accounted for in the information I’ve already provided.

            Please keep in mind, as Dr. Greene points out in his Q&A Blood Types 102, “These are general rules, though, and exceptions apply. Very rarely, gene mutations may change the rules such that “impossible children” become possible.”

            Added:
  469. Lindsay

    I am one of three children born to the same parents and I am the only one with O- blood group, I found my blood group out when I booked in for my first pregnancy and at the time my Doctor raised her eyebrows but did not pursue it, anyhow I have reason to believe that I am not the biological daughter of my Father and my Parents blood types are as follows:

    Mother O+
    Father O+

    Child 1 O+
    Child 2 O+

    Child 3 ( me ) O-

    My Grandfather is the only person in our Family apart from me who has a negative blood group and he is A-

    As I understand it is possible that he passed on a O+- to my Father, but then wouldn’t my Father have A+- blood grouping as I thought that A was always dominant over O? I am confused by the possible permutations to this issue as it could potentially cause a huge split in our Family with my Father questioning his own paternity as well as trying to resolve my Paternity,

    I have ordered a DNA testing kit which my Father and I will both take so we can finally put this issue to rest but any advice reference my Grandfather not being my Fathers biological child would be very appreciated.

    Added:
    • Cheryl Greene

      There is a 6.25% chance that every child of two O+ parents will be O-.

      As to your question about your Grandfather’s blood type and what he might have passed to your father — do you know your Grandmother’s blood type? Without that information it’s just speculation.

      Added:
  470. Anonymous

    DR. Greene her question was can two O+ parents give birth to an O- Baby? You threw a lot of info out there except for the answer. If your parents are both phenotype O+ O+ then their is no way that they could have an O- Baby..But if they are O+ O- hybrids than yes they could just like an AO or BO can have an OO if they marry one because they two are hybrids If an O- O- marries an O+ O+ yes the baby will be O+ O- but if that son or daughter marries an O+ O+ it could be O+ O- but most likely it would be O+ O+. Likewise if an AA+ person marries a OO+ person the children will be AO+ and if an AO+ person marries an OO+ person the child could be OO+ or AO+. That’s how genes work if the AO+ dads O+ sperm happens to attach itself to the moms O+ egg than the baby will be OO+ or if the A+ sperm attaches itself to the O+ egg the baby will be AO+. If the parents are both AO they could have O or O babies and it works the same way with BB OO BO babies as well. AB is extremely rare blood 3.4% of the worlds population have it and 0.6% have AB- all totaling 4% of the worlds population. O is the most and A is a very close second and B blood is kind of rare as well. I hope this helps. I want to note that AO BO and O+ O- A+ A- B+ B- are hybrids where one acts as a silent business partner but yet can be inherited and fully activated. There is no excuse for we have been aware of this for a long time.

    Added:
  471. Michelle young

    I am A neg…is my blood rare? Should I donate my blood regularly?

    Added:
    • Cheryl Greene

      According to the American Red Cross:

      O+ is the most common blood type. Not all ethnic groups have the same mix of these blood types. Hispanic people, for example, have a relatively high number of O’s, while Asian people have a relatively high number of B’s. The mix of the different blood types in the U.S. population is:

       
      Caucasians
      African American
      Hispanic
      Asian
      O +
      37%
      47%
      53%
      39%
      O –
      8%
      4%
      4%
      1%
      A +
      33%
      24%
      29%
      27%
      A –
      7%
      2%
      2%
      0.5%
      B +
      9%
      18%
      9%
      25%
      B –
      2%
      1%
      1%
      0.4%
      AB +
      3%
      4%
      2%
      7%
      AB –
      1%
      0.3%
      0.2%
      0.1%

      The people with O- blood are universal donors. Only 9 percent of people in the U.S. have O-negative blood type. O-negative blood type donors are universal donors as their blood can be given to people of all blood types. Type O-negative blood is needed in emergencies before the patient’s blood type is known and with newborns who need blood.

      People with A- blood are not universal donors, but if you are a healthy person, donating blood is a great way to help others.

      Added:
      • brittney

        If me and my fiance are a type. He is a+ and I’m a- and our son is ab+ is there a possibility of this. Because my fiance is trying to deny it

        Added:
        • Cheryl Greene

          If one parent is A+ and one is A-, their children will be A+, A-, O+ or O-.

          Before jumping to any conclusions, it’s wise to have everyone’s blood tested again. It’s not unusual for there to be an error in one of the three tests, or the recording, or reporting of one or more of the results. If you still have questions, a DNA test of father and child can be used to determine paternity.

          Hope that helps,
          @MsGreene

          Added:
  472. Michelle

    If I am O rh negative and my husband is B positive. What are the possibilities of blood types of our children?

    Added:
    • Cheryl Greene

      Hi Michelle,

      There is a 75% chance each of your children will have B blood type and 25% chance of O. There is also a 75% chance each of your children will have Rh+ blood and a 25% chance of Rh-. So the possible combinations are:

        O+
        O-
        B+
        B-

      Hope that helps.

      Added:
  473. Alison

    I (mother) have O- blood and my daughter has B- blood. Can her dad be a B+ blood type?

    Added:
    • Cheryl Greene

      In this scenario, the father could be B- or AB-. If you have questions, it’s always smart to retest before jumping to any conclusions.

      Added:
    • Candace Brooks

      Same question here.

      Added:
  474. Linda

    When I was pregnant with my son, I found out my blood type, which is A+. I had told my mom. She kind of freaked and said that’s wrong — dad and I have O. I am totally confused. My dad since has passed. His dog tags say he has O, I’m not sure if neg or pos. Can you help me try to figure this out? Thank you.

    Added:
    • Cheryl Greene

      Two O blood type parents can’t have a child with A blood type. It’s not uncommon for one of the three blood types to be reported incorrectly, however.

      Added:
  475. Holly

    My mother is a+ and my father is b+ but I’m o-! There is question if my father is truly my blood father. I was just wondering if that is possible.

    Added:
  476. Nadia

    My mother’s whole family (grandparents, parents and siblings) are all A+ and my dad’s whole family are all O- (grandparents, parents and siblings). My sister and brother are both A+ but I am O+. Am I right in saying that it can’t be correct?

    Added:
  477. Gabywd

    I just found out in my 3 rd pregnancy that I am B – , my husband is O + and both my parents are B + . My first two daughters are B + and at the time I thought I was B+ and I didn’t have any “shots” is this possible? I have been tested 3 times and they all come back B negative very confused !

    Added:
  478. Sarah

    Hello my blood type is O- and my both parents is O+ is that possible???!

    Added:
    • Cheryl Greene

      It is uncommon, but possible. In fact there isa 6.25% chance that two parents with O+ blood will have a child with O- blood.

      Added:
  479. jallusion

    Hi my family all their blood type s are o++ or o+- and I’m the 4 child but I’m the only 1 with b– what’s wrong with that’s?

    Added:
    • Cheryl Greene

      This is possible. For instance, if one parent had A- and the other had B+, they could have have children with either – or + Rh and could have children that are A, B, AB, or O.

      Added:
  480. Elena

    hello,
    I have A+ and my husband has B+, our deceased child was AB-.
    Could this be possible?
    they didn’t find a diagnostic, could be something linked to her blood type?
    thank you so much

    Added:
    • Cheryl Greene

      I’m so sorry for your loss.

      It is possible for an A+ parent and a B+ parent to have a child with AB- blood. I can not tell you if it had any impact on your child’s health. Perhaps you could visit a geneticist for more information.

      Added:
  481. olue

    I am o+ so also my wife but our first daughter was o-. can it be possible? Though we are all AA genotype.

    Added:
  482. Hemant

    is it possible that fathers blood g is AB- , mothers blood g B- …than daughters will be A-….

    Added:
  483. Beki

    Hi I am O- blood type and my daughter is AB- her fathers blood type is unknown, what could his be?
    Because I’ve read that it’s not possible for an O- female to have an AB- baby?

    Added:
  484. Brittany

    I am O+ my daughter is AB- tested at birth due to some complications and I know for a fact that I’m O+ because I received blood… Not the doctor was confused and scratching his head when talking to me about it but… O+ can have AB-

    Added:
  485. Regina

    Hi, my mother is A+, my sisters are A+ and A-, I am O. Is there anyway to decipher what my father’s blood type is?

    Added:
    • smarty p

      is that a homework assignment?

      Added:
      • Jane

        He also could have been A or B or O.

        Added:
        • Cheryl Greene

          Thanks Jane for your answer. I agree :)

          Added:
  486. KB

    O+ mother, A- father. O- negative. Could that be? How is the RH factor determined? I was tested by a blood center because I donate, I was told my childs type by a nurse @ her pediatricians office and the father thinks that’s what his is. Just wanting to double check that a child could be O- if the mother is O+. —-Thank you.

    Added:
    • Cheryl Greene

      A mother with O+ blood and a father with A- blood have a 75% chance of having a child with type A blood and a 25% chance of having type O blood.

      A mother with O+ blood and a father with A- blood have a 75% chance of having a child with Rh+ blood and a 25% chance of Rh- blood.

      For a full explanation, see Dr. Greene’s article Blood Types 101: An Introduction to ABO Blood Types and the Rh System.

      Hope that helps!

      Added:
  487. Carolyn

    I’m an AB- and I just found out my father is O+ can this be possible? I always thought if I was AB- that my parents would have Co-dominant alleles AA, BB, or AB for me to result in AB. SO you can imagine my surprise when I heard that my father is O+ How can this be possible? Unless…

    Added:
    • Cheryl Greene

      That combination is not possible, but blood tests are sometimes wrong as are memories of test results. It’s wise to double check, before making assumptions.

      Added:
  488. Fathimakm

    Sir my mom blood group is A1+ and my father blood group is B+ and my blood group is A1B+. Is this blood group is considered in type of blood group many are telling this blood group is not considered now and weather. Is A1B+ considered?

    Added:
  489. abhaille

    We have three children. I’m O+ and we don’t know what my husband is. Two children are O- and one is O+.

    I’m thinking he’s O-. What are the odds?

    Added:
  490. Anonymous

    sir…i am having AB positive bloodgroup and my wife B positive bloodgroup and my child O positive ..is this possible

    Added:
  491. Alex

    My parents has type O as their blood type. And when I was diagnose with dengue the doctor said that my blood type is AB. Is it possible for me to have that blood type even though my parents are both type O?

    Hoping for your response. Thanks.

    Added:
  492. Nikita

    My blood group is O+ and my Husband is B+ now our child blood group is AB+. Is it possible?

    Added:
    • Cheryl Greene

      Children of an O+ parent and a B+ parent have a 85% chance of being blood group B and a 25% chance of being blood group O. Each child of those two parents have a 93.75% chance of being Rh+.

      Perhaps it’s time to have both parents and the child re-tested. Or consider that one of the parents is not the biological parent.

      Added:
  493. Backatchatwice

    I have a question, not a comment.
    What are the odds of A+ and B+ parents having a B- child?
    Would the A+ mother reject the B- child at some point;
    like with an Rh negative mother and a Rh positive fetus?

    Added:
  494. mary

    Both my parents are deceased. Is it possible to obtain their blood type results from a source somewhere? Mine is rh positive with little c antibodies since the birth of my first child. I would greatly appreciate some help.

    Added:
  495. Jenni

    I recently found out I was blood group A, but my parents both are pretty sure they are both O. If this is correct does this mean they are not my parents?

    Added:
  496. Peter Ngu (Wu)

    I do not know my deceased parents blood types. All my brothers and sisters (7 of them) have Type A Blood type. I am the youngest and have Type O blood type. The one above me is my sister who is 8 years older than me. Is this type of non similarities possible. Hope to hear from you soon. Thank you

    Added:
    • Cheryl Greene

      If one parent has type O blood and the other is type A, 75% of their children would have type A blood and 25% would have type O blood. What that means is each child has a 75% chance of having type A blood and a 25% chance of having type O blood. Theoretically, that means 2 out of 8 children would be type A, but in reality, each child could be either type A or type O.

      For a detailed explanation — Blood Types 102: The Role of A, B, O, and AB Groups In Determining Paternity.

      Added:
  497. EMMA

    I am O+ while my mum is O-. What blood type/group will my father be. This question has been killing me as my mum have no idea and I discovered my dad is type A, could he be my dad? Really urgent.
    Thanks

    Added:
      • savannah Ray

        My mother and father are both O- and I’m O+. Is that possible?

        Added:
        • Cheryl Greene

          If both parents are O-, their children will be O-. But often one of the three parties either don’t remember their test results correctly, or the tests were wrong. Testing errors do happen. Before jumping to conclusions, you should all re-test. If this is a serious concern, paternity testing is the most accurate way to determine who your father is.

          Added:
  498. Annemarie

    if I am O positive and my mother is O positive and my father is AB negative RH does this mean he is a match or not please get back to me asap would appreicaite it thanks x

    Added:
  499. Chanel

    my sister and I have grown up being told we have different dads. We have the same mum. Yet I never met my father. We recently gave blood and found out we are both B- blood. Does this mean we do have the same father? Our parents have passed so we can’t ask them.

    Many many thanks

    Added:
  500. Cleasy

    My wife has O neg blood type and I am AB pos but our son is B neg. I thought AB would have been the dominant type.

    Added:
  501. nessie

    Hi there, both my parents are A+ve and I am A-ve ? According to my family, no one is negative? Can that be? My sister is A+ve.

    Added:
  502. Evelyn Bakic

    I am O+ i have 3 daughters my eldest is O+, second is A+, and the baby is not typed yet. What would be my husbands blood type? He is not a fan of needles so getting him tested just for typing is out of the question.

    Thanks

    Added:
    • anonymous

      Since you are O type and have an O type child and an A type child, this means the other half has to be A type. As per + or – could be either. Your third child can be either an A or O + or -.

      Added:
  503. Clare

    I’m O Rh Negative and we found out my daughter is O positive due to her needing tests when she was very small.

    We also have a little boy who we don’t know his blood group and my husband doesn’t know his – any ideas as to if my son would also be an O positive and would my husband also be O?

    Added:
  504. karysma

    My moms B- and I’m Ab+ and my dad doesn’t really know his blood type. She said he was either B or O. But then I told him I couldn’t be his daughter if he was so I asked him again. Now he is saying he is A+. What should I do?

    Added:
    • Cheryl Greene

      You could have your answer with a simple blood test from your dad. You could say something like, “Dad, I’d like to know the blood types of both you and mom. This could come in handy for health purposes down the road and it would put my mind at ease about our relationship. Is that something you can do for me?”

      Added:
  505. sabina

    I’m O positive and my husband is O negative. Are there chances my child will have rh negative?

    Added:
  506. kerry till

    I’m a rhesus b negative and my sister is ab positive,is it possible we could be full sisters?

    Added:
  507. Febi Francis

    both my parents are o+ and I’m AB- is this possible

    Added:
  508. Diana

    I have a+ blood an my mother is o+ an my father is b+.. I don’t think they are my parent what do I do?

    Added:
    • Cheryl Greene

      You are correct that those combinations can not occur. The first step is to discuss your fears with your parents. They may say they are indeed your biological parents, and one of the blood types is incorrect. It’s pretty easy to have all three of you re-tested. Or this may open the door to a conversation about your adoption.

      If you think there is a possibility that your mother is your biological mother, but your father isn’t your biological father, you may want to talk with her alone before including your father in the conversation.

      Unless you have reason to think your parents are hiding something from you, this should be a calm conversation that simply explains your heritage more fully.

      Added:
  509. Sharon

    Please help. Desperate!
    My Parents both have RH- blood types.
    I am RH+
    How?
    I was born with severe Anemia. .mother needed Rogram shots after me.
    My Uncle is RH+ !!!!
    Please tell me if my parents couldve produced me..or did the someone mess up!!
    Im 54 I dont mind anymore.

    Added:
  510. dt

    I was watching a TV programme where the dad was ab and mum o and the baby was o, so it was concluded that the dad was not at all the dad!

    My eldest sister is type o and our mum is o but dad ab rh negative. I am A rh negative as is my other sister. Could our dad be my eldest sisters dad? She is o positive like mum, but we are all A negative and dad is AB negative! She’s the first born, is she my dad’s? From the info on here she can’t be?

    Added:
  511. Yvonne Shepherd

    I have been diagnosed with chronic kidney disease. It does not run in my dad’s side of the family and I have never met my birth mother So I’m assuming I inherited it from her side. I’m trying to figure out what blood type my birth Mom would be. My Dad is O+ and I am A- rh- factor . Could anyone please help?

    Added:
  512. Jan

    Hi my parents are both O+ I am A- is this possible

    Added:
    • Tina

      No I would be asking your parents some questions sorry but it not possible for to 2 Os to have an A

      Added:
  513. Mark Trevellick

    Can a b poss father and a o poss mother have a o neg baby

    Added:
    • Tina

      Yes

      Added:
  514. Freida

    I have a question, my Dad is O+, but my Mom is A+! My question is, is she my mother?

    Added:
    • Freida

      Sorry just read my question, I am O+ my mother is A+ can she be my mother? My dad was O+!

      Added:
      • Andy

        Yes, if your parents are A and 0, the child can either be 0 or A.

        Added:
  515. figo

    I was tested B+ blood group and my wife to be is 0+ blood group. And in my country, Nigeria, there is this genotype blood that is not familiar to other doctors outside the country and that is AA, AS, SS blood genotype. Universally where does this blood genotypes falls into? Please I will be happy to see my questions answered.

    Added:
  516. Carla

    If both parents have A positive blood, can they have a O negative child ?

    Added:
    • Dr. Alan Greene

      The short answer is yes.

      If two parents both have AO +- genes, they will both have A positive blood and about 1/4 of their kids would be type O and about 1/4 of their kids would be Rh negative, so about one out of sixteen times they would have an O negative child.

      Added:
  517. shefali

    hi…..i belong to india,rajasthan

    Added:
  518. Rohit

    Well b+ is a blood group for a CHILD. Now A+ is mother and O+ is father.
    What is the chance of getting a B+ CHILD??

    Added:
    • Evan

      I don’t think it is possible. According to my Introductory Bioscience lecturer the only way a child can be a member of the B blood group is if one of the parents provides the B to the genotype. In simple terms a member of the A blood group can only be AA or AO while a member of the O blood group can only have oo. As neither parent has the B antigen markers in their blood no offspring of this relationship can be blood group B.

      Added:
      • Sandra

        Dr. Greene,
        Is this reply to the A+ & O+ parents w/ a B+ child correct?

        Added:
  519. Afna

    i’m Afna…My question…..Parents having AB+(Father,Mother)….but children having(1st:AB+,2nd:A+,3ard:AB+).please explain its chances….?

    Added:
  520. shefali

    my sister has blood grp ab+ and both of my parents hav o + is this possible. She is first child of my parents

    Added:
    • Tanvir

      Shefali, can i know where you are from? I am trying to research on this matter…I wont give the verdict, but the cross typing doesn’t really show the possibility of making AB+ out of two O+ parents…But again its all GENETICS…and needs more research! Are you from Bangladesh/India or any of SEA?

      Added:
  521. Catherine

    My parents are both O+ but in a recent test my blood seemed to be B+ is that possible?

    Added:
    • Tanvir

      Are you first child?

      Added:
      • Rohit

        Dear Tanvir,
        Yes I am the first child of my parents .
        Or no???
        Tell me my Blood Group is B+ and Fathers group is O+ my mother is A+.
        Now are they my real parents?? or Tapake Khazuur pe ?

        Added:
    • maddy

      both of my parents are b + n I m o+ but younger sis is b+.., in science, everything is possible so chill

      Added:
  522. pamy

    I am from India, I m a man of O negative blood. Can I marry to O positive women? What will happen to my baby? Can I marry to A blood group? What will happen to my baby? Can I marry to B blood group women? What will happen to my baby? And my last questions is I heard that all the guys who have A negative blood have less genes which lead to no children in life? Is that true?

    Added:
    • abhaille

      You should have no problem marrying any woman that would have you. O negative is the universal donor. Women are the ones that have the trouble having negative blood type when having children.

      Added:
  523. Carol

    Can a person have blood group O and neither parent have that blood group?

    Added:
  524. I. McNutt

    I was born to a mother with AB- and a father as O+. I was the second child and mom never had any shots after her first birth or when carrying me. Can this cause health issues for the second child? And if so what can the issues be? I have had a lot of health issues my entire life one thing after another could this be why?

    Added:
      • Diana Harris

        I can truly relate to I. McNutt in that I’m also the 2nd baby of Rh incompatible parents (my mother being untreated since it was the 1950’s). However, in my case my elder sister was actually the blue baby, born in ’54 she died after just a couple of days.

        I always thought of myself as a miracle baby since I should’ve been the one to suffer that fate being 2nd, yet was born healthy in ’56. When my mother was almost 40 (this essentially was her last chance to have her long desired baby girl).

        I’ve often wondered how I was unscathed, perhaps you can answer this? Anyhow like I. McNutt I’ve suffered a myriad of chronic health ailments even as an adult – between the age of 25-30 is when they presented (psoriasis, psoriatic arthritis, fibromyalgia, chronic fatigue, fibrocystic breasts, hypothyroidism, osteopenia which now is osteoporosis, neuropathy) & have wondered as well if this was connected to the Rh factor situation. I’ve felt like I’m in my 80’s since I was 30 being crippled up in pain, constantly at doctors & labs, medications etc.

        As a child I nearly died from complications of bronchitis when I was 2, had recurrent bouts of hives (even into adulthood) & the usual childhood illnesses (measles, mumps, chicken pox). I’ve been severely nearsighted since I was 7 (Coke bottle glasses) which now has put me at high risk for some type of retinal detachment & bleeding so must be monitored at least every 6 mos. I’m 58, but the last 30 years (when I was still relatively young) have really drained me & I’ve a hard time envisioning another 30 years of pain & struggle.

        I can’t help thinking if my health conditions stem from the Rh issue then something could be done that would target the source & I finally could get better. I recently was diagnosed with major depressive disorder & that has to do with all of this & how life is getting harder for me – just to do the basics. On the Yahoo Q & A another Rh person had written similarly how they’ve suffered with their health & their siblings had all died by their 40’s.

        Have there been any studies done of babies (born prior to 1963) of Rh incompatible parents & their health outcomes as they mature? Are those of us writing in who are sick merely flukes? is the Rh incompatibility & illness just coincidental or is there a pattern & one worth investigating? I welcome & would be most grateful for any information & opinions you could provide.

        Added:
  525. John J

    If both parents are O+ , and they have three kids that are O+. Is it possible for a fourth child to be O-?

    Added:
      • olu

        I am an o+ so also my wife but our first daughter is o negative. Can it be possible? Though we are all AA genotype.

        Added:
  526. stumped

    I have 2 children with o+ blood type, I am o+ and my husband is o+, he has a daughter from another woman and this daughter has ab- blood type, the daughter says her mothers blood type was also ab-. Is is possible that this is his daughter?

    Added:
    • Cheryl Greene

      IF the mother’s blood type is AB, it is not possible for the father to have O blood type. A mother with AB and a father with O blood type would have children that are either A or B, but not O or AB. The odds of A or B are equal. But in this situation, you can not confirm the mother’s blood type and there are many reasons why the mother might not be what the daughter thinks she is — daughter remembers incorrectly, mother wanted the daughter to think they had the same type so said what she thought would be true, mother lied, tests were incorrect, etc.

      Added:
      • CIS-AB

        Another possibility is that other woman has the Cis-AB mutation, which would make it possible for the father to have group O blood.

        http://en.wikipedia.org/wiki/Cis_AB

        Added:
  527. payal

    My brother blood group is “O”positive and my sister in law blood group is “AB” negative but my nephew blood group is “B” positive it is possible or not?? Plz help us..

    Added:
    • Cheryl Greene

      It’s not the most common blood type from this mother and father, but this is possible.

      Each person receives an A, B, or O gene from each parent. In this system, the A and B genes are co-dominant and the O gene is recessive. In other words, both parents must have type O blood for their children to have type O blood.

      Added:
  528. Rose

    My parents were blood o group but my brother is a resus negative mine is a possitive can this be ??

    Added:
    • Cheryl Greene

      From the information you’ve given, it’s impossible to know for sure. If both your parents were O- all their children would be negative, but if either of them were O+, this is a possible combination.

      Added:
  529. christy

    Yes my blood type is ab+ and one of my daughters just found out her blood type is b- Her father is adopted and he doesn’t know his blood type. There is a chance he could not be the real father, so what would his blood type have to be to be compatible for him to be the real father? Please help!!!

    Added:
    • Cheryl Greene

      Your daughter’s father would have blood type A+, B+, AB+, or O+.

      Hope that helps.

      Added:
  530. Edward Hines

    My mom is O+ and dad is B+, how can I be A+, help please?

    Added:
    • Linda

      Hello Edward,
      Did your question ever get answered?
      I have the same situation and further digging has pulled up some anomalies that could make this true…

      Added:
    • omar

      Hi Edward.
      genetics has the answer! although, it looks not possible with Mendel’s rule of inheritance, these rules could be broken!! you or one of your parents could have a mutation somewhere! or one of your parents could have a blood type “genetically” different from what is appear to be in their blood “phenotype”!! in other way, one of your parent might have a “hidden” A gene that is not appeared in their blood phenotype!! this hidden A gene carried on sperm or ovum of your parents and passed to you!! it is worth thinking to go for genetic test this may solve the “unexpected” outcomes.
      hope i clarified it to you. thank u.

      Added:
  531. Glen

    My parents and brothers and sisters are all O type not sure about pos/neg. Why am I AB positive? Is there something my parents should tell me?

    Added:
    • C

      Maybe there’s something at least one of your parents should be telling you. And your dad. :)

      Added:
      • Cheryl Greene

        Before jumping to conclusions, you may want to consider a few key questions:

        • Was I wanted?
        • Do my parents love me?
        • Will it hurt my father if I open this can of worms?

        You may have been a much desired child that your parents were able to conceive with the help of a sperm donor.

        Or one of the three tests may be wrong.

        Added:
    • omar

      Hello Glen,
      if you consider “mutation”, that is possible!!! you and your parents are advised to do genetic testing for clarification of these (rare) outcomes. if you exclude blood type test error.

      Added:
  532. sabillah

    My parents both are o+ and mine is B+. Is that possible? I’ve been wondering.

    Added:
    • Cheryl Greene

      Two O+ parents can’t have a B+ child, but consider:
      — Perhaps all the tests aren’t correct. Test errors do happen.
      — Perhaps someone’s memory of his or her test results are wrong.
      — Even “impossible” results happen. They are very rare, but genetic mutation is real.

      If this is of concern, consider DNA testing to determine paternity.

      Added:
  533. nav

    sir…i am having AB positive bloodgroup and my wife B positive bloodgroup and my child O positive ..is this possible??

    Added:
  534. Chris

    I saw a case where both parents are O+ but all their children are A+. How can i reconcile these?

    Added:
    • Pat

      Both my mom and dad are gone, both of them are 0 positive, including my brother , but I am A Positive

      Added:
  535. marwan john

    am b negative and my wife o negative it is posssible we have a positive child ???

    Added:
  536. Shirley

    Father A negative Mother O Negative child A positive. Is it possible this man to be the dad?

    Added:
    • Ashleigh

      YES… II just had my son 2 days ago… I am A- and his father is O+… Our son is A+… A type is dominate over O type and when you have a – + combo the + is dominate… So you would end up with an A+ Baby…

      Added:
  537. Courtney

    My mother is ab negative and my father is o negative. I’m o negative. How is this possible if an ab blood type can’t parent a o blood type?

    Added:
    • Michelle

      I am almost 100% sure that my husband tested AB-. I was pregnant and found out to be negative, so we tested my husband. I am O-, both my children are O- as well. The only reason I say almost 100% sure dad is Ab, is because after reading this article I began to question my memory..lol..I cannot find the labs report to check for sure. But after this article, I’m extremely curious to find out for sure. Just sharing.

      Added:
  538. Mainlay Jasn

    Suresh Mathur … My mother is O+. My dad is O+, but I’m O-. My little brother is O+.
    So, you’re wrong.

    Added:
    • Alexis Brown

      He is not wrong however, you are mistaken. Each person has 2 RH factors either ++, +- or –. He explained all variables in his examples.

      Added:
      • Courtney

        Mainlay was speaking to someone who commented and was wrong. Js.

        Added:
  539. Suresh Mathur

    Hi,
    Me and my wife both blood group is O+, and my new born baby boy also O positive.
    I think that if parent are O+, all baby will O+.
    Thanks Doc For nice article.

    Added:
  540. Liana Hernandez

    Hi my blood type is A + and my husbands is A- so when our child was born she was an O + . We took a DNA test to confirm which proved this can happen.

    Added:
  541. patty balser

    If I have RHO negative blood, what would my parents blood have to be?

    Added:
  542. subir dutta

    my blood groupe is A ..and my wife is B …but my son’s groupe is O ..is it possible

    Added:
    • Alka Gupta

      Yes.. It it is possible coz u have A group means u r carrying A nd O gene nd ur wife have B group means she is carrying B and O gene…so ur baby can take one O from u nd another O from ur wife nd ur baby’s blood group vil be O

      Added:
    • davidpaulabraham

      My wife and i are 0+ what is my baby blood group???

      Added:
    • Srinivas

      Mother A positive,Father B positive.child O negative.Is it possible

      Added:
  543. mich

    Hallo

    Can a baby’s blood be B+ if the mother is A- and the father is type O (not sure if – or +)?

    Please help.

    Added:
    • Harsha

      I just saw your query…..i am not good at biology it cannot be possible to have B+ if parents are A- and o(+ or -)….you just refer to this link http://www.endmemo.com/medical/bloodtype.php ….. the result i got is NO

      Added:
    • Alka Gupta

      No it is not possible… One of the two parents must have B gene … Otherwise it is not possible.

      Added:
  544. tyshauna joiner

    Can o positive people have a healthy baby?

    Added:
    • anita k

      We are both o+. Won’t our baby have difficulties in health?

      Added:
  545. Rajesh p

    Docter I am simply verifing my blood group is O positive and wife blood group is B positive but my baby is b positive it is possible sir

    Added:
  546. yash

    THANK YOU SIR I HAVE FOUND THE ANSWER FOR MY QUESTION IN THE ARTICLE BLOOD TYPES 102

    Added:
  547. yash

    Sir,I have a question my cousin’s parents are B+ and my elder cousin brother has B+ but the case of his younger brother he has O+ IS THIS POSSIBLE ? Please reply to this on my mail address.
    THANK YOU

    Added:
  548. chantelle

    As I understand I was a “blue baby” during birth and needed an emergency blood transfusion.

    My Mother is A+
    My Father is A+
    But I am AB+ (this is impossible because two A… cant produce an AB)

    Can this be caused due to the blood transfusion that I receaved after my mother gave birth to me?

    Added:
  549. Aaron Forrest

    Hi my mother is o negative. I don’t know what my fathers blood type is, but mine is ab positive. Research I have done on the internet says this is impossible. Can some one please explain?

    Added:
    • Courtney

      Your father might have ab blood. it does say an ab can’t parent an o

      Added:
  550. Kyle

    Both the wife and I have O+ blood. How can we have a baby with A-? I understand that we both are (+,-) so we can have a child that is O- but how is it that the baby is A? The doctor told us that this is very rare. I just want to understand how.

    Added:
    • Becky

      I am very interested in any answers you find on this subject, Kyle.

      I am very obviously not adopted, but just recently I found out that both my parents are type O (dad is O+), two out of three siblings are O+ (one sister doesn’t know her type), and all three of my children are O+. I am type B (I don’t know whether its positive or negative). To my knowledge I’ve never had a blood transfusion. Everything I’ve searched online states that this is not possible.

      Added:
      • Fiona

        I’m very interested in what you have found out as well. Both of my parents are O+ and I am B+. I’m just very confused as from my very basic Biology it’s not possible?

        Added:
    • Sabrina

      Same has happened to me and my husband. He is o- and I am o+ but our daughter was born A+. I hear about this happening in many other cases.

      Added:
  551. Jules

    Hi my mom is an o+ and my father is a b- and I found out during the labs for my pregnancy that I’m an a+. That isn’t possible is it?? I have other reasons to be suspicious but does medically prove that it is impossible for them to both be my biological parents?

    Added:
  552. Anushree

    So my mom’s blood group is B-ve while my dad’s is B+ve, but I’m AB+ve. They say that in rare cases it is possible for the blood group not to match, but I’m still skeptical about it. Can you help?

    Added:
  553. Katie webb

    My blood type is b-and my twins are o-my ex husband doesnt think he is the father but his blood type is o- as well could that mean he is the dad

    Added:
    • Tish

      I’m O- and my son is O-, my husband is O+, there is no question he is from us both as he was born by in vitro fertilization.

      Ha ha — unless he was ‘switched’ at birth, but highly unlikely-he looks like both of us no doubt.

      Added:
  554. "M"

    My mom is A+ , my sister is O- and I am B-. Is this possible and so we have the same dad?

    Added:
  555. love

    What about pregnancy if my blood group is b- and my wife o+?

    Added:
  556. Rajesh p mysore

    Docter sir I’m confused. My blood group is O positive and my wife’s blood group is B positive and my son blood group is B positive. Is it possible?

    Added:
    • Henk

      Yes, this is possible.
      The gene types of blood group B are BB and BO. The gene types of blood group O is OO. Your child must have gene type BO (the B inherited from your wife and the O inherited from you) making him having blood group B.

      Added:
  557. sai

    If you have parents with same O+ blood, would it be possible if they bear an A+ offspring? Please answer because I really want to know if I am really their daughter.

    Added:
  558. Larry Richardson

    Hi Dr. Greene.

    Both of my parents are deceased. When my mother was alive, she told me she had the rarest form of blood: AB negative. My father’s dog tags, from the military, indicate that he was O positive.

    From photographs and time sequences for conception, there are doubts that the man I called father is really my blood father. The disparities in physical characteristics, the manner in which we were treated growing up, and our psychological makeup are extremely distinct. My brother was the first born, and has blood type O negative. I am O positive.

    I am now 71 years old and only wish to verify if or not I was the love child of another second lieutenant while my father was in amphiibious training for the Normandy Invasion on D-Day.

    I have asked my brother if he talked about it with my mother since I left the house at 18 years of age and never returned until 20+ years later. He and my mother were best buddies and often palled around together. He says she never spoke of it. When I bring up the subject of how different we are in every aspect of our lives (physio, psychological, upbringing, etc.), he simply dismisses the subject with, “What does it matter?”

    Although I am an engineer, I have difficulty understanding the biology of blood types and Rh factors. Biology was not my forte in college!

    Thank you,

    Larry Richardson
    Los Lunas, NM

    Added:
    • Lucy

      Hi
      I am not an expert, but from what I have been reading about blood types, I think your mother was mistaken in saying she was AB negative…
      To have O children she would have to have an O in her genes, for example she would have to have been AO or BO.
      An AB mother would produce either an A or B baby I think…
      I could be wrong but this is my understanding.
      Maybe you could check this specific fact out.
      Lucy

      Added:
    • Sam

      Larry, perhaps I can hep put you mind at ease. I have the exact scenario in my family, and this is how a geneticist explained it to me. “This reminds me of a case in Japan. There an AB man and his O wife had an O child. Lots of research later, the researchers showed that he had his A and B genes stuck together on one chromosome and a “blank” spot on the other. What that means is that he could either pass AB to his kids or O and so with an O wife, he could only have O and AB kids.Another possibility is that dad has a really rare blood type called Bombay. These folks look O but genetically can be any blood type. If this were the case, then you and your brother might have the same blood type. Like I said, this is extremely rare.”

      Added:
  559. Rock

    My blood type is A negative my father is O rh positive what can my moms blood type can be and please what if both my parents have O positive are they really my parents please answer I am worry about:!?

    Added:
  560. Connie Jones

    Hi Doc: My brother and I are adopted and have been told that we are both from the same mother. Birth mother says, No, that she miscarried a boy before she had me out of wedlock… Long story..
    My question to you is..Can a sibling with A+ blood type and the other sibling with O- (Me)…be related?
    Just curious. Thank you..

    Added:
  561. Bridget

    i am confused …OK i have O- blood type and my Husband thinks his is A+(from blood test he did back in high school ).. we have 5 children all are O- so is that possible or is he really A-

    Added:
    • KIMBERLY ROBBINS

      I am trying to figure out the same thing during this pregnancy because I am trying to avoid getting a rhogam shot if my husband is positive, however, my husband is not sure whether he is positive or negative. I am O negative and my husband is A (something). All my kids (3 of them) are O negative as well.

      If your husband is positive, he could be ” ++ ” or “+ – ” which would still make him positive. If you are negative, then you are ” – – ” So, when you you do the calculations, your kids have the possibility of coming up “AO” which is simply “A”….OR….”OO” which is simply O. This is because you both pass on one letter to the child. For your kids to be O and your husband to be A, he HAS to be “AO”.

      As for the RH factor, he HAS to be “+ – ” so he can pass on a negative to the kids just like you. That would allow them to be O negative. So, yes, it is possible for him to be positive.

      Added:
      • Rajesh

        Docter I am simply verifing my blood group is O positive and wife blood group is B positive but my baby is b positive it is possible sir

        Added:
  562. san

    My blood group is O+. My wife’s blood group is B. My son’s blood group is AB. Is that possible?

    Added:
  563. sravanthi

    Both of my parents are B positive and I am B negative. This is possible?

    Added:
  564. Freda Arthand

    My daughter and I have the same blood type — O positive. Her dad (I think that’s he dad) has AB. We did a swab test and it was suppose to be her dad. However the guy I was with also had O positive blood. Could it be possible that the other guy is the father to my daughter? The one with ) Positive blood?

    Added:
  565. JC

    My sister is an O blood type. My mother is AB and my father is O. Is that even possible? Are they my parents or am i adopted?

    Added:
  566. patrick clancy

    if you have two parents one with o- blood and one with o+ positive blood is it possible to have two siblings with O negative blood and the other with o+positive

    Added:
    • Henk

      Yes, this is possible. Rhesus positive can have gene type ++ or +-. If one of your parents have +- and produce a child with a — gene type (Rhesus D negative; see explanation by Dr Greene), siblings can have both +- (Rhesus D positive) and/or — (Rhesus D negative).

      Added:
  567. Lisa

    Both my parents are O, my two siblings are O, but I am A. Is this possible?

    Added:
    • April

      No, two O make O

      Added:
  568. Ann

    What does it means if the baby have a A+blood type, and the mother is o and the father is o. A little confuse. Can you give me the answer
    Thank you

    Added:
    • Migdalia

      Doctor I don’t understand why my child came out with A+ blood type but me and my spouse have O+… Please help

      Added:
  569. mical

    Dear Dr….me and my wife are A positive …what shall my children blood group. ? I really like to know. .Thanks

    Added:
  570. Alexis

    I’m becoming concerned whether or not my parents are my biological parents. Everyone in my family has O++ blood and I’m O-, plus I don’t resemble any family members. I don’t know what to do?

    Added:
  571. Gyasi Dennis

    Both my parents have type O,but i have type B-,please is it normal?

    Added:
  572. Ashley Chambers

    Okay i need help understanding i am not sure of mine or my parents blood types i do know my sister is o begative with rh negative does this mean i too will be rh negative.? My next question is i have been cleared from a dr saying i have no fertility issues as has my husband but in 8 years were not parents yet is it possible that our blood types could be not compativ
    ble causeing us not to be able to get pregnant?

    Added:
  573. TheOtherRosie

    That sounds simple enough. Parents each have 2 genes that determine the blood type of their offspring. Each parent shares only 1 of their 2 genes with their offspring. The dominate gene determines the offspring’s blood type. I’ve been out of college for a long time. I didn’t have much science in college, but I’m making up for it now. Enjoyed your article very much. Genetics is so very interesting. Thank you for sharing. : )

    Added:
  574. now confused over bloodtyping

    ok, my first husband was O+ and so am I , our child is O-, my second husband is A+, me O+ and our child is A-… how is this?

    Added:
    • kim

      You = O + – (positive is the dominant gene and negative recessive)

      First husband same.

      You both gave your recessive gene to your child.

      Second husband will have to be A+ –

      Your second child will be AO blood type (A being the dominant and O recessive) and like your first husband you both gave your recessive – to your child.

      Hope this helps.

      Added:
  575. Jacqueline Gardiner

    I remember talking with ny genetics instructor about this. Both my parents are rh positive. My Dad had issue believing I was his because I’m rh negative. Initially she said no, its not possible for two positives to have a negative. My heart fell through my stomach. As I turned to walk away she yelled “wait a minute!” I learned that one of them carries the recessive gene. Pretty cool stuff.

    Added:
  576. Ravi Bhatia

    my son is ab positive , me & my wife are both b positive. is it possible?

    Added:
    • Cody

      I don’t think so. To have a b type blood you have to have two genes that are either BB or Bo. If two people make a baby that have B type blood it is either BB+BB or Bo+BB or BB+Bo or Bo +Bo. There is no A in the mix to make AB child.

      Added:
  577. kat

    Okay, my parents are rh+ both of them. what would i be?

    Added:
  578. april

    My blood type is B- HR what would my parents blood types be?
    I have 2 kids and they both have AB+, I was given the rhogam shot during and after both my
    prengnecies, why?

    Added:
  579. Chris

    Please help…. I’m confused,.. My blood type is B positive and my mothers is A negative, is this possible ?

    Added:
    • Michelle Patterson

      Yes. Your father must have been B positive. Everyone actually has TWO letters (one from each parent) and TWO Rh signs. So since you are B+ you are either BO++ or BO+- (BB++ or BB + – would also be type B+ but that can’t be you, because of your mother she had no B to give you or it would show in her blood type. ) Your mother, being A- is actually either AO– or AA– She could have given you the O. Obviously she didnt give you a B, which is why you are BO not BB.) If she had given you the A you would be type AB. So she gave you the O. She definitely gave you the – since she only has – – . So she gave you O – and your father must have given you B+ which means you are BO+- which would be interpreted as type B+

      Added:
  580. anne

    helloo,i had a question pls kindly give me an answer .Is it normal that the father ,mother ,and a daughter had same blood types?coz one of my friend family they had all O POSITIVE blood types.

    Added:
  581. Emma Lane Davis

    i am in my first pregnancy and my blood type is A- and i have Rh- blood yet my mother has A+ and my Dad has O+ and they are both Rh+. my dr tested my blood thats how i know i’m A- and Rh-. but i don’t understand how this is my blood type and my parents are both positive.

    Added:
    • Cody

      For you to have A- blood your parents would both have to have receive Rh-. So your mom could have AA+- or Ao+- and your dad would have oo+- .

      Added:
  582. jayson

    hi my parents are both os and i’m ab are they my really parents?

    Added:
    • Marisol Torres

      I am a mom that has O- and my husband has O+, both of the kids that I gave birth to are AB+ Even though teachers have asked our kids if they were adopted, my kids know they were not adopted. So it is possible! I guess rare, but possible ;)

      Added:
      • jayson

        thank you :)

        Added:
        • Marisol Torres

          You are welcome!

          Added:
  583. Julie Balfour

    My mum is 0+ I am 0- what blood type could my father be?

    Added:
    • Kezia Elizabeth

      B, A or O positive or negative

      Added:
  584. Joanne Jackson

    My mother is B I don’t. Know positve or negative my dad is a postive but I always thought my step dad which is o postive was my dad is it possible?

    Added:
  585. Heather Hylemon

    I have a question both my parents are o blood type but im a+ an my sister is o as well how is that possible

    Added:
  586. Stephen Maria Jarrells

    My dad is an O- my mom is an O+ but I am absolutely B- Rh-…does anyone have an answer? My mom refuses to talk & unsure what hospital i was born my dad says he’s my dad and dont mind a blood test. Plz help

    Added:
  587. lorraine wallace

    I am o negative reh both my parents are b+ how is this possibly. ???

    Added:
    • Cody

      O and Rh- are recessive genes. Even if someone has them it will not show in their blood type unless they have both of them. So your parents would have to be Bo+- for you to be oo– which is O-.

      Added:
  588. Jannette Davidson

    Both my parents are O+, so are all my siblings. I am A+ and my mother swears she never had an affair. I also have very dark skin, no widow peak, and unattached earlobes. Please figure that one out.

    Added:
    • Cheryl Greene

      Here is more information for you from Dr. Greene –http://www.drgreene.com/unders… One thing to to consider, your blood type could be an error. Before you go any further, consider having your blood type re-tested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

      Added:
      • Jannette Davidson

        I am sure my blood type is correct. I don’t think the U.S. Army, the V.A. hospital and all the times I have donated blood could be wrong. We all know out blood type from getting tested when my grandpa and step dad needed to find a match for kidney disease. From what I gather there is a thing called a genetic mutation, can this be the cause?

        Added:
        • Cheryl Greene

          I don’t know if it could be genetic mutation. That’s a great question. Does anyone else here know?

          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

          Added:
          • R Quispe

            According to the following website there is still a very very small possibility of genetic mutation

            http://genetics.thetech.org/ask/ask181

            However, if you are still unsure, only a DNA test will give you peace of mind.

            Added:
  589. desteny

    I have a question my sister had her period on novrmber 8 on the 14 she have relationship with one man on december 11 she was in another relation with someone else in january she found out she was pregnant acording to the doctor she consive on december 27 and her due date september 19 she had the baby premature she is A positive the father is Rh o positive and the baby is o positive can that happen

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  590. april

    Hi there,
    Me and my sister are 1yr. and exactly 18 days apart same mom and dad. We have blood type RH O negative and we both have to take the RohGam shot. Now I was told by an RN that it’s impossible for us to be from the same parents and have this blood type. That only one child will come out with RH O negative. Is this true???

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  591. Me Trost

    Question: I am Blood Type O+ and my Brother is Type A+. What Blood Type combination(s) would our parents (RIP) have to of had for me (Sister) to be O+ and Brother to be A+?

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  592. Noelito Zipagan Glorial

    pls answer, how about parents with O type, and the child is A??is this possible??pls answer

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  593. Rose

    I am A-, my sister is A+, my brother is O+………is it possible that we have the same mother and father? There are doubts that we have the same father. We think we have the same mother but our father is the ?

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  594. Cheryl Boisoneault

    I am RH-A negative . My Mom is O positive and my Dad is B positive …How did this happen?

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  595. rj

    hi good eve. i have a question regarding my blood type my parent is A blood type me is B negative is it really my parent

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  596. Mohammed Mubeen

    Hi, i hav a question that my blood group is AB and Rh positive and my wife is O+ and Rh negative so what will be the result for this…?? and if she has O= and Rh positive then what will be the result…??????

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  597. Miranda Decker

    Here’s an odd one. My parents are both o+, so is my sister… I am A negative. So… I’m really starting to wonder how this would be possible….

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    • Cheryl Boisoneault

      Same here did you get an answer? my parents are positive to and both my brothers as well None have A blood…Or are they negative..my blood type is A negative RH ? I would love to know how this happened

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    • Mela

      My parents are both 0 + , me and my brother are 0 – . And its totally fine because 0+parents can only give birth to babies with 0+ or 0 – blood type. In our case it happened to be 0- . :)

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    • Charla Satterwhite

      Miranda, did you ever find the answer to your question? Because I need to know the same thing.

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      • mariya

        My blood group is a positive and my husband o positive. But our son o negative. Is it possible. ?

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        • Mariane

          I am A+ and my husband is O+ and our son is O- too. This is possible so don’t worry.

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  598. Miss Jennie

    My dad belongs to B type blood and my mom belongs to O type blood, whereas my brother belongs my dad’s blood type but how come my blood group is A positive?

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  599. Peggy Robinson

    Can a RH Negative and A O Have a A positive Child?

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  600. Peggy Robinson

    Can A RH Negative And a O Have an A positive child?

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  601. Miriam LuvEtte Saucedo

    My parents are both B+ … Why am i A+?

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    • Subasis Mishra

      Is it possible that baby having A+ve if both parents have B+Ve blood group?

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  602. Nean

    my mother has 0 Negative RH blood group – bit of confusion as my fathers dog tags of 1947 simply have 04 blood type…he told me they both have RH O Negative…and his is rare – I am O Positive – born in 1958 in an out back town in the Northern Territory where blood transfusions for the baby be non existent…very confused…my younger brother definitely theirs RH factor child severe anger issues, learning difficulties speech, tactile…I am 55…my parents told me I was adopted they are both in their late 80’s and with cancer I am their carer mum is now in full time care…could you please tell me is it possible for two O negative Rh blood groups to have children…my brother is fine now but was an out of control toddler and child and violent…thanks so much they do not wish to discuss my adoption which is fair enough.

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  603. island boy

    Hello, I have a question. Can both parents with type O blood produce a type A+ child? Both my parents are type O and i am type A+. Switches in the hospital can happen to where i am coming from. Please help!

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    • Huckle_Cat

      I think he answered this question in the paragraph where he says, “if two parents both have type O blood, all of their children will have type O blood.” That is because they can only pass on a type O gene to their children.

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    • Jaclyn Elaine

      My parents are both o+, and me and my twin sister are ab+ so we have been wondering this as well. There is no question of paternity or switching at birth as we are splitting images of our parents, and we are pretty confident in the results of the blood tests

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    • Cheryl Greene

      Here is more information for you from Dr. Greene — http://www.drgreene.com/understanding-blood-types/ One thing to to consider, your blood type could be an error. Before you go any further, consider having your blood type re-tested.

      I hope that helps.
      Best, @MsGreene
      Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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    • Michelle Patterson

      No. If both of your parents are type 0, they could NOT produce a type A child.
      It is possible that either one of the three of you is incorrect about your blood type. It is still possible they are both your parents if either of the three of you is incorrect about your blood type. Or possibly one of them is not your parent. If you are 100% certain you are type A then you HAD to get that A from one of your biological parents, either your father or mother. Your mother could be type O, but then your father would have to be type A, or vice versa

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      • rochelle

        Is it possible if that both parents have B+ positve blood type. and im B +positive

        is it possible The DNA. results Is Negative results…

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        • Cheryl Greene

          Hi Rochelle,

          Blood types are very general. DNA results are specific.

          In other words, two B+ parents are not eliminated from the possibility of being the parents of any B+ child. But they are not necessarily the parents of any specific child.

          Each person has unique DNA and each of their children carry part of it. DNA results are considered accurate.

          I’m very sorry if this is not the answer you’re looking you’re seeking.
          Best, @MsGreene
          Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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        • Sam

          is it possible for me to have 0+ blood type when my father is ab+ and my mother is b+

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          • Cheryl Greene

            Sam,

            Our current understanding of genetics is that it is not possible for a parent to be AB blood type to have a child with O blood type. An AB parent can only have children who are A, B or AB.

            It’s not uncommon for blood types to be different than they are thought. It is wise to have all your blood retested.

            I hope that helps.
            Best, @MsGreene
            Note: I am the co-founder of DrGreene.com, but I am not Dr. Greene and I am not a doctor. Please keep that in mind when reading my comments and replies.

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Comments are closed.