Hemophilia is caused by several genetic factors; one, a recessive allele of an X- linked gene, is the subject of this problem. Assume that a man with hemophilia marries a normal woman whose father had hemophilia. What is the probability that they will have a daughter with hemophilia?

Question

Quizplus · Accepted Answer

The woman is a carrier (XHXh) since her father had hemophilia (XhY). The man has hemophilia (XhY). Their daughter must inherit an X chromosome from each parent, so the probability of her being XhXh (having hemophilia) is 1/4.

Hemophilia Is Caused by Several Genetic Factors; One, a Recessive