If one parent is a carrier of the cystic
fibrosis gene, while the other parent does
not carry the allele-- Can their child have
cystic fibrosis? Explain why
An individual must inherit two non-functioning CF genes – one from each parent – to have CF. If both parents are carriers there is a 1 in 4 (25 percent) chance that both will pass on the non-functioning gene, which would result in a pregnancy affected with cystic fibrosis.