Zoology - Principles of Inheritance and Variation Question with Solution | TestHub

In family A, if both the parents are homozygous recessive, both should be diseased and should have 100% diseased progeny. In family B, if both parents are homozygous dominant, they would not have got the recessive disease in the first place. In family B, if both are heterozygous recessive, then also they would not have got the disease, neither 80% of progeny would be diseased.