If a color-blind (X-linked recessive trait) man marries a woman who is heterozygous for the trait, whatproportion of their male offspring can be expected to be color blind?
A) 1/2
B) 1/4
C) 1/8
D) 3/4
E) 100 (all)

Question

Quizplus · Accepted Answer

Since color blindness is an X-linked recessive trait, a color-blind man (X^cY) married to a heterozygous woman (X^CX^c) will pass his Y chromosome to all male offspring, and the female will pass either an X^C or an X^c chromosome. Therefore, 50% of their male offspring will receive the X^c from their mother and be color blind.

If a Color-Blind (X-Linked Recessive Trait) Man Marries a Woman