You are a genetic counselor, and a couple comes to you with concerns that if they have a child together, he or she

could have hemophilia. Neither of them has hemophilia, but the woman's biological father did have an X-linked recessive
form of hemophilia. How should you advise them?



a. Half of their children will have hemophilia.
b. All of their sons and half of their daughters will have hemophilia.
c. None of their children will have hemophilia, but all of their daughters will be carriers for hemophilia.
d. Each of their sons will have a 50% chance of having hemophilia, and each of their daughters will have a 50%
chance of being carriers.
e. All of their sons will have hemophilia, and all of their daughters will be carriers.


ANSWER: d

Biology & Microbiology

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