Can O and A Blood Type Parents Have a Child with B Blood Type?

Q: Can O and A Blood Type Parents Have a Child with B Blood Type?

Hello： The ABO blood group system is characterized by the presence of A antigen (type A), B antigen (type B), both antigens (type AB), or the absence of both antigens (type O) on the red blood cell membrane. <br>The genes responsible for producing A or B antigens are inherited in

Questions about blood types?

Hello, doctor: Can you tell me what blood types the children of an O type and an A type couple might have? Is it possible for them to have a child with B type blood?

Meimei, 20~29 year old female. Ask Date: 2007/10/08

Dr. Yang Wangjun reply Obstetrics and Gynecology

Hello: The ABO blood group system is characterized by the presence of A antigen (type A), B antigen (type B), both antigens (type AB), or the absence of both antigens (type O) on the red blood cell membrane.
The genes responsible for producing A or B antigens are inherited in a dominant manner.
If one of the two homologous chromosomes inherited from the parents carries the gene that produces A antigen (for example, in type A), the phenotype will express A antigen (i.e., type A).
The same applies to type B.
Therefore, an individual with phenotype A can have a genotype of AA, AO, or OA (where the O allele does not produce A or B antigens).
An individual with phenotype B can have a genotype of BB, BO, or OB.
An individual with phenotype AB can have a genotype of AB (AB AB), AB O, O AB, A B, or B A.
An individual with phenotype O can only have the genotype OO, meaning that all gametes (sperm or egg) produced by type O individuals will have the O genotype.
Type A individuals can produce gametes with genotypes of AA, AO, or O.
If a type A individual has the genotype AA and mates with a type O individual, the offspring will necessarily be type A (AO).
If a type A individual has the genotype AO and mates with a type O individual, the offspring could be either type A (AO) or type O (OO), but it is impossible for them to have a type B child.

Reply Date: 2007/10/08

More Info

When considering the blood types of parents and the potential blood types of their children, it's essential to understand the basic principles of genetics, particularly the ABO blood group system. In this system, there are four primary blood types: A, B, AB, and O. The blood type is determined by the presence or absence of antigens on the surface of red blood cells, specifically A and B antigens.

In your case, one parent has blood type O and the other has blood type A. Blood type O is characterized by the absence of both A and B antigens, while blood type A can be either homozygous (AA) or heterozygous (AO). This means that the A parent can pass on either an A allele or an O allele to their child.

To analyze the possible blood types of the children from these parents, we can use a simple Punnett square. Here are the possible combinations:
1. If the A parent is homozygous (AA):
- Possible combinations with O parent (OO):
- Child's genotype: AO (Blood type A)
- Child's genotype: OO (Blood type O)
2. If the A parent is heterozygous (AO):
- Possible combinations with O parent (OO):
- Child's genotype: AO (Blood type A)
- Child's genotype: OO (Blood type O)
From this analysis, we can conclude that the children of an O type parent and an A type parent can only have blood types A or O. There is no possibility for them to have blood type B.
Blood type B can only occur if at least one parent contributes a B allele. Since the O type parent does not carry any A or B alleles, and the A type parent can only contribute an A or O allele, the offspring cannot inherit a B allele from either parent.

In summary, if one parent is blood type O and the other is blood type A, the possible blood types of their children are A or O. There is no genetic pathway for these parents to produce a child with blood type B. If there are concerns about the blood types of the parents or the child, it is advisable to conduct a blood type test to confirm the results.

Similar Q&A

Understanding Baby Blood Types: What to Expect from O and A Parents

Hello, I have some questions to ask you. My relative has a baby; the mother is type O and the father is type A. What blood type will the baby have? Could it be type AB?

Dr. Gu Qingxian reply Pediatrics
Hello, please recheck the blood types, including those of the parents and the child. Kindly visit Mackay Memorial Hospital's pediatric department. Thank you!

Understanding Bombay Blood Type: Can It Be Inherited?

My parents have blood types A and B, my paternal grandfather is type A and my paternal grandmother is type O. My maternal grandfather is type AB and my maternal grandmother is type O, who is suspected to have the Bombay blood type. My mother has a brother with blood type AB, and ...

Dr. Huang Shaoxin reply Family Medicine
Based on your description, you may also have the Bombay blood group, although the probability is very low. Therefore, it is recommended that you undergo blood type testing and a saliva test (to measure A, B, and H antigens in saliva) to confirm whether you have the Bombay blood g...

Do Liver Transplants Require Matching Blood Types?

Is it necessary to have the same blood type for a liver transplant? If I need a liver transplant in the future, since I am type O and my wife is type B, and her entire family has hepatitis B, only my wife and children do not have hepatitis B. Children born from an O type and a B ...

Dr. Xu Jinchuan reply Gastroenterology and Hepatology
Hello! If you need a liver transplant, you can only receive type O blood. In principle, it's best to have the same blood type for a liver transplant to reduce the risk of rejection. However, type O blood can be donated to others, but individuals with type O blood can only re...

Exploring Kidney Donation: Testing, Confidentiality, and Blood Type Compatibility

Since my father is currently undergoing dialysis at your hospital, witnessing his struggles and inconveniences has motivated us, his children, to consider kidney donation. I would like to know if it is necessary to have the evaluation done at your hospital. Which department and w...

Dr. Yao Quan reply Internal Medicine
Dear Ms. Ooariel, Hello. I greatly admire your filial piety. If you wish to undergo kidney donation evaluations at Taoyuan General Hospital, please consult with Dr. Wu Ching-Tang from the Department of Surgery. Dr. Wu specializes in kidney transplantation at our hospital. Living...