Question

Why the father never passes on the gene for haemophilia to his son?

Answer 1

Explanation:

Answer: Haemophilia is a sex-linked recessive disease. The defective gene is present on the X chromosome only and not on the Y chromosome. As the father always contributes a Y chromosome and never passes an X chromosome to his son, the gene for haemophilia can never be passed from a father to his son.

Answer 2

Explanation:

Haemophilia is a sex-linked recessive disease. The defective gene is present on the X chromosome only and not on the Y chromosome. As the father always contributes a Y chromosome and never passes an X chromosome to his son, the gene for haemophilia can never be passed from a father to his son.