A man and his wife are both heterozyous for the sickle-cell trait. The likely percentage of their offspring that will be either carriers or sicklers is?

A. 75%
B. 50%
C. 25%
D. 100%

Correct Answer:

Option A – 75%

Explanation

An heterozygote for sickle-cell anaemia = AS

Crossing two AS persons, we have one AA, two AS and one SS.

∴ The probability that the children are either carriers or sicklers = 34
= 75%