Red-green color blindness is an X-linked recessive trait in humans.A color-blind woman and a man with normal vision have a son.What is the probability that the son is color blind?
A)100%
B)75%
C)50%
D)25%
E)0%

Question

Quizplus · Accepted Answer

Since the mother is color-blind, she has two X chromosomes with the recessive allele (XcXc). The father has normal vision, so he has one normal X chromosome and one Y chromosome (XY). The son inherits one X chromosome from the mother and one Y chromosome from the father, resulting in XcY, which means he will be color-blind. Thus, the probability is 100%.

Red-Green Color Blindness Is an X-Linked Recessive Trait in Humans