Principles of Inheritance and Variation Question 171

171. Haemophilia is more commonly seen in human males than in human females because: [2005]

(a) a greater proportion of girls die in infancy

(b) this disease is due to a Y-linked recessive mutation

(c) this disease is due to an X-linked recessive mutation

(d) this disease is due to an X-linked dominant mutation

Show Answer

Answer : c

Hints & Solution

(c) This disease is due to an X-linked recessive mutation. Males suffer from this disorder since they have only one X chromosome and hence express any trait on this chromosome.