You are examining a human pedigree for a trait. You notice that an offspring can be affected even if neither parent is affected. This immediately tells you that the trait is:
A)dominant.
B)recessive.
C)epistatic.
D)produced by multiple alleles.
E)incomplete penetrance.

Question

Quizplus · Accepted Answer

If an offspring can be affected even if neither parent is affected, this suggests that the trait is recessive. This means that both parents are carriers of the trait, but do not express it themselves. When two carriers mate, there is a 25% chance that their offspring will inherit two copies of the recessive allele and therefore express the trait.

You Are Examining a Human Pedigree for a Trait