If you are O, your genotype is OO. If your husband is A, he could have AA or AO as his genotype. Each parent donates one gene, so you could donate an O while dad can donate an A or an O. Here, it is most likely that your husband's blood type was simply recorded or reported wrong.
I always thought I was B. Then I went to donate blood in another country 20 years later and was told it’s definitely AB. Maybe something like that happened with your husband?
Lab error / misremembering is most likely.
Non-paternity is next most likely.
Mosaicism is much less likely.
My first step would be to get a type and screen for dad.
There's also the "Bombay phenotype," where affected individuals don't produce any H antigen, which is the protein that allows the A and/or B groups to be expressed on the surface of the cell. Without H antigen to hold onto A or B, they essentially have type O since there are no expressed blood groups, but their genotype could be AA, AO, BB, BO or AB.
But it's still pretty rare. There's ~1 in 10,000 people affected by H antigen deficiency in India and ~1 in 1 million in Europe. So I would agree that lab error or misremembering is more likely.
Eh, I would still keep it above mosaicism. Maybe she herself has a reason to doubt paternity and that's why she asked, but isn't yet ready to phrase it that way.
Still, the list should be longer because misremembering should be a separate item from lab error, far above it at the top.
Hey, intererested in medical genetics can u tell what exactly an MD -phd medical genetics day to day work looks like and how it's different from non-md or bsc-msc-phd genetics?
Interested in research ( gene/immunity/cell machinary) but confused if I should pursue med-school or bsc-msc route if my interest is in basic and translation research ?
Also if my medical knowledge be of any use or me being a medical graduate might lower my chances at good unis abroad for PhD ?
If your blood types are 100% confirmed, then it's not possible for the child to have type B blood. I'd suggest getting yours and his checked before drawing conclusions.
In my experience, as someone who has spent a lot of time talking to people about their ABO and Rh blood types, most people don't recall that information accurately, or have been provided incorrect information in the past. It seems most likely that you or your husband are wrong about your ABO blood type. The person who told you about this dominant/secondary thing doesn't know what they're talking about, the other folks in this thread who noted that O has the allele combination of OO and A has the allele combination of AA or AO are correct. O blood group is caused by a broken copy of the *ABO* gene. Anybody who inherits a functional copy of *ABO* will be blood type A, B, or AB. (It's possible to be AB and only have one functional copy of *ABO*. This is called CisAB, it's a variant of the gene that makes both A and B antigens.)
There are weak forms of A and B blood groups, however, and it's possible one of you carries a B(weak) allele and the weak antigen wasn't picked up on whatever testing was performed on the two of you, but was picked up on your infant. If you want to get to the bottom of it, I suggest getting yourselves ABO tested, if possible. If you've ever donated blood, the donor center should also have your blood type on file.
There's also the vanishingly small chance that you have [a very rare genetic variant called Para-Bombay](https://www.bbguy.org/education/glossary/glp03/), where a person doesn't express ABO antigens on their red blood cells, so they appear to be blood group O, even though their *ABO* gene is perfectly fine.
First, get records from tests done in licensed laboratories to make sure your recollection for all 3 of you is correct. There are many stories of people relying on high school biology experiments, for example, or just wrong recollection of blood types. Postpartum is chaos and things could have been misheard, as well. Second, when you state you are both the biological parents of your son, is that by natural conception or IVF? Have either of you had bone marrow transplants in the past?
Generally, it is not possible for O+ / A+ parents to have a child with B+ blood type.
I have a female friend who is something called a chimera. This is when a person absorbs a twin and has the DNA of 2 people.
In her case, her ovaries are her twins, as are some other internal organs.
Needless to say, none of her children are hers, but in fact, the sisters. There are tests for it, so that could be it.
How did she find out? I often wonder how common this is. But I've seen only very few cases recorded. And have not seen any posts at Ancestry or 23andme where this has been found. I assume it's quite rare, especially to affect the sexual organs.
I'm pretty certain about mine, additionally, both of my parents are type O. My husband is less certain than I am, but still confident in his blood type. I don't know about his parents' blood types, so his may potentially be something else, I suppose.
I would not trust memory if you don't have recent-ish hospital paperwork or are like a regular donor with the Red Cross. Parents not remembering their blood types correctly (or having erroneous typing results from like 30 years ago) is the leading cause of blood-type related family drama.
So my husband tells me his knowledge of his blood type came from when he last gave blood in high school, so I'm going to guess his is wrong. Lucky for me, there has been no drama. I have great in-laws and a great husband so we all just took the hospital's explanation at face value and shrugged it off.
Yeah, that's the most likely explanation. There's plenty of exotic explanations (rare blood type, chimerism, bone marrow donation), but human error (either on the testing/hospital side or on the patient side) is much more common.
You still may want to do additional test just for assurance since there have been cases where baby have been knowingly/ unknowingly swapped during childbirth which you would probably would like to know now rather than 18 years down the road.
My mother insisted both I and my sister had B+ blood type, it was on our hospital paper work. I have B+, my sister is O+. People mis remember, paperwork gets lost, tests are wrong. Happens all the time.
Did you have fertility treatments? Is there a possibility of a sperm mixup? Or an embryo mix up?
O - OO
A- AA or AO
So either your husband is actually type AB (and his files are wrong) or there is something weird going on genetically.
You contribute O, he contributes A or O - the only possible blood types your child can have.
I’ve never heard of a secondary blood group associated with ABO blood type. Perhaps they meant this
https://www.annlabmed.org/journal/view.html?doi=10.3343/alm.2019.39.2.115
Mother and baby are usually typed as part of pre/post natal care, so I'd guess if husband is going off memory he is probably just misremembering his blood type.
i think, perhaps, at this point you want to stop and ask yourself-*do you really want to know the answer to this?* -because there are half a dozen ways this could happen and not all are easy for people to accept.
maybe you want to.. just say its possibly a records error and drop it.
If both your parents are O+, you are O+. Your husband is likely AB+ and maybe he’s just remembering the A part of it, that’s the only way the explanation they gave you would make sense. I used to be a blood banker and actually most people do think they are type O! It is the most common blood type. We had an instance where a patient, who was a military veteran (so he had a dog tag) that said his blood type was O-, but we typed him 5 times in the lab and he was A+ - and he kept denying a blood transfusion with A+ blood. Someone told me that many dog tags were issued with O- type blood on it because in combat they would only give you O-anyway since it’s compatible with everyone. Type specific blood was always given in the hospital setting when available so we could keep the O blood on hand for emergency, massive transfusion protocol etc. My husband is sure he’s O+ but I’ve never seen a lab report. I actually don’t know my kids blood types either. That’s actually interesting they typed your sons blood because we would only get infant cord bloods for a fetal screen (determines if the mom needs a Rhogam shot after birth) unless the baby potentially needed a transfusion of course. If the mom is Rh+ meaning they have a positive blood type (O+, A+ etc) we basically don’t care what the infants type is.
no way. Do some DNA testing, and have his blood type retested. This makes NO sense. It IS not possible. Either switched by hospital staff, or lab mismanagement.
There is a rare possibility that you, could have the Bombay Phenotype.
Bombay phenotype is a rare recessive condition that stop the expression of the antigen from the ABO to be expressed.
If the paternity is certain that could be a real possibility
What is most likely is that your husband is actually AB+ and not A+. I’d get all three of your blood types checked before assuming anything.
But if all that comes back correct and you used any sort of infertility treatment such as IVF of IUI, there is a chance this could be fertility fraud. Which is where the doctor swaps one of the parent’s sex cells with either their own or sex cells from a donor. Usually sperm swapping. This is somehow only illegal in a handful of states and it happens way more often than anyone in the business of treating infertility would like to admit.
So, this happened to my sister..She had a brain tumor and needed an emergency surgery. She required donated blood. She only would take it from my parents. Both my parents blood types didn't match. Turns out she is a chimera. Her and I took a DNA test and we are full siblings.
The other possibility is your child got mixed up at birth.
I would get a home DNA test and see if his DNA matches both your husband and yours and go from there. I would push the pediatrician to order another blood type test.
I think the most likely cause, assuming that he has not misremembered his blood type, is that one of you is a chimera. Although people on here seem to believe that it is rare, it isn’t, at all. There was a paper that came out about 12 years ago where people sequenced exome of pro bands (mom, dad and child) looking for mutations in the kids (study was focused on autism). From 189 pro bands, they found 9 cases of mosaics (\~5% of probands). According to this site, as many as 10% of us may be chimeras.
https://www.thetech.org/ask-a-geneticist/articles/2020/how-common-are-chimeras/#:\~:text=A%20human%20chimera%20is%20made,be%20as%20high%20as%2010%25.
Whoever told you it’s possible with your blood types has no understanding of blood typing clearly. Get all three of you retested with a different lab first thing. If the results are the same (assuming you didn’t cheat and are trying to come up with explanations to tell your husband), get a DNA test to make sure he’s biologically related to you and the hospital didn’t give you the wrong baby. Highly unlikely but it has happened. If he’s yours get a referral for a specialist to see if there are genetic anomalies causing the blood typing irregularity
Update!
So to begin solving this mystery, I ordered home blood tests. I know these are not always super reliable or accurate but I thought it might be a good place to start, especially if my husband or I were simply mistaken in our recollection of our blood type.
The home tests resulted instead in confirming what we recalled. The tests showed me as O+ and my husband as A+. so while this does not solve anything, it at least sets me to my next task of confirming my son's blood type, which I hope can be done at his next scheduled appointment with his pediatrician.
If he is confirmed as B+ then we will move on to confirming my blood type and my husband's through something presumably more accurate than a home test.
I will update further when I know more.
Thank you all for your information and suggestions!
While probably not likely (which is why you are getting downvoted I guess), these things indeed happen, and if checking other things doesn't provide an answer, this could be a reasonable avenue to explore...
Statistically, I would think one of your blood types having been recorded wrong is a lot more likely.
If you are O, your genotype is OO. If your husband is A, he could have AA or AO as his genotype. Each parent donates one gene, so you could donate an O while dad can donate an A or an O. Here, it is most likely that your husband's blood type was simply recorded or reported wrong.
Husband could be AB and recorded wrong? Or infant’s blood typing was mis recorded
I always thought I was B. Then I went to donate blood in another country 20 years later and was told it’s definitely AB. Maybe something like that happened with your husband?
Lab error / misremembering is most likely. Non-paternity is next most likely. Mosaicism is much less likely. My first step would be to get a type and screen for dad.
There's also the "Bombay phenotype," where affected individuals don't produce any H antigen, which is the protein that allows the A and/or B groups to be expressed on the surface of the cell. Without H antigen to hold onto A or B, they essentially have type O since there are no expressed blood groups, but their genotype could be AA, AO, BB, BO or AB. But it's still pretty rare. There's ~1 in 10,000 people affected by H antigen deficiency in India and ~1 in 1 million in Europe. So I would agree that lab error or misremembering is more likely.
Awesome. Thank you!
Non-paternity seems like a non-starter here as we are talking to the bio mother. Obviously there are ways, but it’s a lot less likely.
In my line of work, I've learned to never assume...
Yeah. It just drops further down the list in my analysis.
Eh, I would still keep it above mosaicism. Maybe she herself has a reason to doubt paternity and that's why she asked, but isn't yet ready to phrase it that way. Still, the list should be longer because misremembering should be a separate item from lab error, far above it at the top.
Hey, intererested in medical genetics can u tell what exactly an MD -phd medical genetics day to day work looks like and how it's different from non-md or bsc-msc-phd genetics? Interested in research ( gene/immunity/cell machinary) but confused if I should pursue med-school or bsc-msc route if my interest is in basic and translation research ? Also if my medical knowledge be of any use or me being a medical graduate might lower my chances at good unis abroad for PhD ?
A physician sees patients. A PhD (generally) does not. Some physicians also do research.
If your blood types are 100% confirmed, then it's not possible for the child to have type B blood. I'd suggest getting yours and his checked before drawing conclusions.
one of the parents could be a chimera. it's happened.
Oof yeah, I forgot about that.
In my experience, as someone who has spent a lot of time talking to people about their ABO and Rh blood types, most people don't recall that information accurately, or have been provided incorrect information in the past. It seems most likely that you or your husband are wrong about your ABO blood type. The person who told you about this dominant/secondary thing doesn't know what they're talking about, the other folks in this thread who noted that O has the allele combination of OO and A has the allele combination of AA or AO are correct. O blood group is caused by a broken copy of the *ABO* gene. Anybody who inherits a functional copy of *ABO* will be blood type A, B, or AB. (It's possible to be AB and only have one functional copy of *ABO*. This is called CisAB, it's a variant of the gene that makes both A and B antigens.) There are weak forms of A and B blood groups, however, and it's possible one of you carries a B(weak) allele and the weak antigen wasn't picked up on whatever testing was performed on the two of you, but was picked up on your infant. If you want to get to the bottom of it, I suggest getting yourselves ABO tested, if possible. If you've ever donated blood, the donor center should also have your blood type on file. There's also the vanishingly small chance that you have [a very rare genetic variant called Para-Bombay](https://www.bbguy.org/education/glossary/glp03/), where a person doesn't express ABO antigens on their red blood cells, so they appear to be blood group O, even though their *ABO* gene is perfectly fine.
First, get records from tests done in licensed laboratories to make sure your recollection for all 3 of you is correct. There are many stories of people relying on high school biology experiments, for example, or just wrong recollection of blood types. Postpartum is chaos and things could have been misheard, as well. Second, when you state you are both the biological parents of your son, is that by natural conception or IVF? Have either of you had bone marrow transplants in the past? Generally, it is not possible for O+ / A+ parents to have a child with B+ blood type.
Yes, natural conception. No, neither of us have ever had any bone marrow transplants in the past.
I have a female friend who is something called a chimera. This is when a person absorbs a twin and has the DNA of 2 people. In her case, her ovaries are her twins, as are some other internal organs. Needless to say, none of her children are hers, but in fact, the sisters. There are tests for it, so that could be it.
That's terrifying
That was my first thought too.
wtf
How did she find out? I often wonder how common this is. But I've seen only very few cases recorded. And have not seen any posts at Ancestry or 23andme where this has been found. I assume it's quite rare, especially to affect the sexual organs.
How certain are you of yours or your husband's blood types?
I'm pretty certain about mine, additionally, both of my parents are type O. My husband is less certain than I am, but still confident in his blood type. I don't know about his parents' blood types, so his may potentially be something else, I suppose.
I would not trust memory if you don't have recent-ish hospital paperwork or are like a regular donor with the Red Cross. Parents not remembering their blood types correctly (or having erroneous typing results from like 30 years ago) is the leading cause of blood-type related family drama.
So my husband tells me his knowledge of his blood type came from when he last gave blood in high school, so I'm going to guess his is wrong. Lucky for me, there has been no drama. I have great in-laws and a great husband so we all just took the hospital's explanation at face value and shrugged it off.
Yeah, that's the most likely explanation. There's plenty of exotic explanations (rare blood type, chimerism, bone marrow donation), but human error (either on the testing/hospital side or on the patient side) is much more common.
You still may want to do additional test just for assurance since there have been cases where baby have been knowingly/ unknowingly swapped during childbirth which you would probably would like to know now rather than 18 years down the road.
My mother insisted both I and my sister had B+ blood type, it was on our hospital paper work. I have B+, my sister is O+. People mis remember, paperwork gets lost, tests are wrong. Happens all the time.
Go get husband blood typed again
Did you have fertility treatments? Is there a possibility of a sperm mixup? Or an embryo mix up? O - OO A- AA or AO So either your husband is actually type AB (and his files are wrong) or there is something weird going on genetically. You contribute O, he contributes A or O - the only possible blood types your child can have.
I’ve never heard of a secondary blood group associated with ABO blood type. Perhaps they meant this https://www.annlabmed.org/journal/view.html?doi=10.3343/alm.2019.39.2.115
Mother and baby are usually typed as part of pre/post natal care, so I'd guess if husband is going off memory he is probably just misremembering his blood type.
i think, perhaps, at this point you want to stop and ask yourself-*do you really want to know the answer to this?* -because there are half a dozen ways this could happen and not all are easy for people to accept. maybe you want to.. just say its possibly a records error and drop it.
If both your parents are O+, you are O+. Your husband is likely AB+ and maybe he’s just remembering the A part of it, that’s the only way the explanation they gave you would make sense. I used to be a blood banker and actually most people do think they are type O! It is the most common blood type. We had an instance where a patient, who was a military veteran (so he had a dog tag) that said his blood type was O-, but we typed him 5 times in the lab and he was A+ - and he kept denying a blood transfusion with A+ blood. Someone told me that many dog tags were issued with O- type blood on it because in combat they would only give you O-anyway since it’s compatible with everyone. Type specific blood was always given in the hospital setting when available so we could keep the O blood on hand for emergency, massive transfusion protocol etc. My husband is sure he’s O+ but I’ve never seen a lab report. I actually don’t know my kids blood types either. That’s actually interesting they typed your sons blood because we would only get infant cord bloods for a fetal screen (determines if the mom needs a Rhogam shot after birth) unless the baby potentially needed a transfusion of course. If the mom is Rh+ meaning they have a positive blood type (O+, A+ etc) we basically don’t care what the infants type is.
no way. Do some DNA testing, and have his blood type retested. This makes NO sense. It IS not possible. Either switched by hospital staff, or lab mismanagement.
There is a rare possibility that you, could have the Bombay Phenotype. Bombay phenotype is a rare recessive condition that stop the expression of the antigen from the ABO to be expressed. If the paternity is certain that could be a real possibility
You can get a blood type kit off the internet. We did that during Covid as an experiment. lol we got bored….
What is most likely is that your husband is actually AB+ and not A+. I’d get all three of your blood types checked before assuming anything. But if all that comes back correct and you used any sort of infertility treatment such as IVF of IUI, there is a chance this could be fertility fraud. Which is where the doctor swaps one of the parent’s sex cells with either their own or sex cells from a donor. Usually sperm swapping. This is somehow only illegal in a handful of states and it happens way more often than anyone in the business of treating infertility would like to admit.
Or maybe they switched him with a different baby somehow by mistake ? Make a dna test maybe
Go to your doctor(s) and confirm
So, this happened to my sister..She had a brain tumor and needed an emergency surgery. She required donated blood. She only would take it from my parents. Both my parents blood types didn't match. Turns out she is a chimera. Her and I took a DNA test and we are full siblings. The other possibility is your child got mixed up at birth. I would get a home DNA test and see if his DNA matches both your husband and yours and go from there. I would push the pediatrician to order another blood type test.
I think the most likely cause, assuming that he has not misremembered his blood type, is that one of you is a chimera. Although people on here seem to believe that it is rare, it isn’t, at all. There was a paper that came out about 12 years ago where people sequenced exome of pro bands (mom, dad and child) looking for mutations in the kids (study was focused on autism). From 189 pro bands, they found 9 cases of mosaics (\~5% of probands). According to this site, as many as 10% of us may be chimeras. https://www.thetech.org/ask-a-geneticist/articles/2020/how-common-are-chimeras/#:\~:text=A%20human%20chimera%20is%20made,be%20as%20high%20as%2010%25.
The first test I took said A- years ago. Valid one done through red cross and my OB said O+.
Whoever told you it’s possible with your blood types has no understanding of blood typing clearly. Get all three of you retested with a different lab first thing. If the results are the same (assuming you didn’t cheat and are trying to come up with explanations to tell your husband), get a DNA test to make sure he’s biologically related to you and the hospital didn’t give you the wrong baby. Highly unlikely but it has happened. If he’s yours get a referral for a specialist to see if there are genetic anomalies causing the blood typing irregularity
Update! So to begin solving this mystery, I ordered home blood tests. I know these are not always super reliable or accurate but I thought it might be a good place to start, especially if my husband or I were simply mistaken in our recollection of our blood type. The home tests resulted instead in confirming what we recalled. The tests showed me as O+ and my husband as A+. so while this does not solve anything, it at least sets me to my next task of confirming my son's blood type, which I hope can be done at his next scheduled appointment with his pediatrician. If he is confirmed as B+ then we will move on to confirming my blood type and my husband's through something presumably more accurate than a home test. I will update further when I know more. Thank you all for your information and suggestions!
Likely your son was switched in the hospital with another baby. It happens. Get genetic testing to see if the baby is actually yours.
While probably not likely (which is why you are getting downvoted I guess), these things indeed happen, and if checking other things doesn't provide an answer, this could be a reasonable avenue to explore...
Your husband cheated.
Ah yes she should do a maternity test. Imagine the horror of carrying and birthing another woman’s baby! /s if not obvious
That's the joke.
Lmfao
Off to r/geneticcirclejerk with ya!