Question

How is it possible for an offspring to exhibit a recessive trait if neither parent exhibited that recessive trait? What must be true about the parents’ genes for this to occur?

Answer 1

(you have to know that only 1 allele is passed on from each parent to each offspring and that alleles are different variations of a gene) Recessive alleles are "masked" by dominant alleles, so a person exhibiting the dominant trait could have both dominant alleles or one of each, while the recessive phenotype must have both recessive alleles. If, A=dominant allele, a= recessive allele then, "AA" or "Aa" = dominant and "aa"= recessive so, for the offspring to express the recessive trait (by acquiring 2 recessive alleles (1 from each parent)), both parents have to be Aa.

Answer 2

0-0

Answer 3

ok.....maybe a more simple expalnation? x'D