Question

A haemophilic man marries a normal-homozygous woman. What is the probability that their son will be haemophilic ?

• A. 75 %
• B. 50 %
• C. 25 %
• D. 0 %

Answer 1

Answer: (D)

0 %

Haemophilia is a sex-linked recessive disorder that has its been on the X chromosome. If a man is hemophilic and the female is normal homozygous female then none of their sons will be haemophilic because they will receive one of their X chromosomes from the mother and as the mother is normal, the genes will not be transmitted.

So there are zero per cent chances of being hemophilic.

So, the correct option is '0 %'