In: Biology
You are working as a genetic counsellor. A newly married couple comes to you for advice. Neither the man nor the woman has cystic fibrosis, but both have full siblings with this genetic disease. Cystic fibrosis is an autosomal recessive disease caused by a single locus and is typically diagnosed by the time a child is 2 years old. The young couple are planning to start a family and are worried about the risk that they might conceive a child with cystic fibrosis. Based on the information provided here only, what is the probability that a child of this couple would have cystic fibrosis?