Question

What would be the best way to predict the probability of a baby having cystic fibrosis?

Answer 1

⊕ANSWER⊕

• To have cystic fibrosis, a child must inherit one copy of the cystic fibrosis transmembrane conductance regulator (CFTR) gene mutation from each parent.

• People who have only one copy of a CFTR gene mutation do not have CF.

• They are called "CF carriers."

Each time two CF carriers have a child, the chances are:

• 25 percent (1 in 4) the child will have CF

• 50 percent (1 in 2) the child will be a carrier but will not have CF

• 25 percent (1 in 4) the child will not be a carrier of the gene and will not have CF

People with CF can also pass copies of their CF gene mutations to their children.

If someone with CF has a child with a CF carrier, the chances are:

• 50 percent (1 in 2) the child will be a carrier but will not have CF

• 50 percent (1 in 2) the child will have CF