Human Genetics Problem Set

Problem 1: Inheritance of an X-linked recessive trait

Correct!

Red-green color blindness is X-linked in humans. If a male is red-green color blind, and both parents have normal color vision, which of the male's grandparents is most likely to be red-green color blind?

A.	maternal grandmother
B.	maternal grandfather In this problem, an X-linked recessive allele is passed from an affected male, to a daughter who is a heterozygous carrier, and subsequently to an affected grandson.
C.	paternal grandmother
D.	paternal grandfather
E.	either grandfather is equally likely