In humans, ABO blood groups are controlled by codominant alleles. A person with genotype I^A I^B will have which blood group?

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Question

In humans, ABO blood groups are controlled by codominant alleles. A person with genotype I^A I^B will have which blood group?

Accepted Answer

Blood group AB — Because I^A and I^B are codominant, both alleles are fully expressed in the phenotype, resulting in blood group AB. Neither allele masks the other, which is the defining feature of codominance.

Answer

Blood group AB

Answer

Blood group B

Answer

Blood group O

Answer

Blood group A

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