Principles of Inheritance and Variation Question 173
173. A man with a certain disease marries a normal woman. They have eight children (3 daughters and 5 sons). All the daughters suffer from their father’s disease but none of the sons are affected. Which of the following mode of inheritance do you suggest for this disease?
(a) Sex-linked recessive
(b) Sex-linked dominant
(c) Autosomal dominant
(d) Sex-limited recessive
Show Answer
Answer : b
Hints & Solution
(b) The daughters receive one $X$ chromosome from the father and one $X$ chromosome from the mother. Since all the daughters suffer from their father’s disease, the $X$ chromosome from the father must be carrying a dominant trait.
