12. A child has blood group O. If the father has blood group A and mother blood group B, work out the genotypes of the parents and the possible genotypes of the other offsprings.
If the child has O blood group than it is evident that parents are heterozygous. Thus, the genotype of the father will be and that of the mother will be . The child having blood group O will have genotype . The other children may have genotypes (A blood group), (B blood group) and (AB blood group).