Question

Haemophiliac man marries a normal homozygous female. The probability of their child being haemophiliac is?

• A. $0.00\%$
• B. $25\%$
• C. $50\%$
• D. $75\%$

Answer 1

The correct option is A $0.00\%$

Genotype of father and mother:
Father – X*Y
Mother – XX
So the offsprings will be of the genotype:
X*X
X*X
XY
XY

The girls will be the carrier for the haemophilia gene and are normal whereas the boys will be normal because the mother is normal.

So, the correct answer is '0.00%'.