Principle Of Inheritance And Variation Question 405
Question: Haemophilia is mentioned as a trait carried by the mother and passed to her sons. What is the pattern of inheritance for this trait?
Options:
A) Haemophilia is an allele carried on one of the mother’s autosomal chromosomes.
B) Haemophilia is an allele carried on the Y chromosome because more males have this genetic disorder than females.
C) Haemophilia is an allele carried on the X chromosome and can be directly inherited by the son from the father or the mother.
D) Haemophilia is carried on the X chromosome and can only be inherited by the son if the mother is a carrier.
Show Answer
Answer:
Correct Answer: D
Solution:
[d] Haemophilia is an X-linked trait, and can only be inherited by the son from his mother’s X chromosome.
The father contributes the Y chromosome to his son (not his X chromosome) and thus, cannot pass any of his X-linked alleles to his son.
BETA
