Question

A haemophilic man marries a normal (non-carrier) woman. What is the possibility of them having a daughter suffering from haemophilia?

• A. 0%
• B. 50%
• C. 75%
• D. 100%

Answer 1

The correct option is A

0%

For the daughter to suffer from haemophilia, both the X chromosomes would need to have the gene for haemophilia. However, since the woman is a non-carrier, only one chromosome (from the father) will have the gene for haemophilia. Therefore, while none of the daughters will suffer from haemophilia, all of them will be carriers.