Question

A man with x-linked recessive colour blindness mates with a woman who is not colour blind herself, but whose father also has x-linked colour is the probability that this man and woman will have a child who is colour blind?

a. 1/2
b. 1/8
c. 3/4
d. 1/4

Answer 1

The probability that the man and woman will have a child who is colorblind is 1/2 or 50%.

Step-by-step explanation:

The probability that the man and woman will have a child who is colorblind is 1/2 or 50%.

Color blindness is an X-linked recessive trait, which means it is carried on the X chromosome. Since the man is colorblind, he must have an X chromosome with the colorblind gene. The woman, who is not colorblind herself, can be a carrier if her father has color blindness.

When the man and woman have a child, there are two possibilities:

1. The child inherits the mother's X chromosome with the normal gene for color vision and the father's X chromosome with the colorblind gene. In this case, the child will be a carrier like the mother and will not be colorblind.
2. The child inherits the mother's X chromosome with the colorblind gene and the father's Y chromosome. In this case, the child will be a male with color blindness.