Question

In familial hypercholesterolemia, individuals homozygous for the allele causing the disorder completely lack receptor while individuals homozygous for the normal allele are phenotypically normal. This is an example of

A) codominance

B) epistasis

C) incomplete dominance

D) complete dominance

Answer 1

The right answer is C.

Incomplete dominance is when hybrids of the F1 generation have an intermediate phenotype (between the two phenotypes). That is, in the case of familial hypercholesterolemia, if the subject is heterozygous it will have 50% functional receptors compared to a healthy homozygous subject.