When two or more genes influence a trait,an allele of one of them may have an overriding effect on the phenotype.When an allele has such an overriding effect,it is said to be:
A) Dominant
B) Recessive
C) Penetrant
D) Epistatic
E) Expressive

Question

Quizplus · Accepted Answer

When one gene's expression overpowers another gene's expression, it is referred to as epistasis, and the allele that exerts the overriding effect is referred to as an epistatic allele. Therefore, the answer is choice D, "Epistatic." A dominant allele exerts its effects over a non-dominant allele, but it does not necessarily affect the expression of a completely different gene, and penetrance refers to the proportion of individuals with a specific genotype who exhibit the expected phenotype. "Expressive" is not a common genetics term and is not related to the concept described in the question.

When Two or More Genes Influence a Trait,an Allele of One