Suppose You Are a Genetic Counsellor, and a Man and Woman

Multiple Choice

Suppose you are a genetic counsellor, and a man and woman come to you with concerns that if they have a child together, it could have cystic fibrosis. Also suppose that genetic tests reveal that the woman is a carrier for cystic fibrosis but the man is NOT. Which of the following is the best advice you could give them?

A) Each child that they produce will have a 50% chance of having cystic fibrosis, and the other 50% will be carriers.
B) They should not have any concerns, because no child that they produce should have cystic fibrosis.
C) No child that they produce should have cystic fibrosis, but each of their children will have a 50% chance of being a carrier.
D) Each of their offspring will have cystic fibrosis.