Question

18. If three children in a family have blood groups O, AB and A, the genotypes of the parents must
be__and

Answer 1

To have a child with O blood group, both parents should have at least one IO allele. Genotype in option A has all three required alleles; IA, IB, IO; these heterozygous parents will form three types of gametes with three different alleles and can have progeny with B (IB IO), AB (IA IB) and O (IO IO) blood group.

Answer 2

Answer:

A,AB

Explanation:

If someone has blood type A, they must have at least one copy of the A allele, but they could have two copies. Their genotype is either AA or AO. Similarly, someone who is blood type B could have a genotype of either BB or BO. A blood test of either type AB or type O is more informative.