Is it possible to have a child with type o blood if both parents are not type O? Thanks.
Yes, it is possible for parents who are not type O to have a child with type O blood.
ABO blood types are inherited. A personâs blood type is determined by the inheriting 1 of 3 different forms of a gene (called alleles) from each parent – in this case – A, B, or O.
If a person has 2 A alleles â they have A blood type. If they have 1 A allele and 1 O allele they have A blood type, because A is dominant over O.
If a person has 2 B alleles â they have B blood type. If they have 1 B allele and 1 O allele they have B blood type, because B is dominant over O.
If a person has 1 A allele and 1 B allele â they have AB blood type. AB alleles are co-dominant, so they both show up.
If a person has 2 O alleles â they have O blood type.
Both A and B forms of the gene are dominant over O. If you have a child who has O blood type, then you would expect the parents to be either A blood type (which means the parent has AO genotype) or B blood type (which means the parent has BO genotype). In this case, the parents each have a 50-50 chance of passing on the O genotype. If they child receives both O alleles (one from each parent), the child will then have the O blood type.
For more information:
Go to the Inherited Disorders and Birth Defects health topic.