What are the chances of inheriting cystic fibrosis if one parent has trait?

Zero: In order for any possibility of a child acquiring cystic fibrosis (cf), both biological parents would have to have the CF trait as carriers. CF is known as an autosomal recessive disease, which means both parents have to be carriers in order for their child to possibly acquire the disease. In these cases, when both parents are carriers, there is a 25% chance the child will acquire cf.

Close to zero: CF is autosomal recessive, you need to inherit a defective copy of the gene from each parent. Baring spontaneous mutation or some similarly rare event, both parents need to have the gene to inherit the disease.

Depends: This depends on the profile of the other parent. Their are dozens of mutations that can lead to CF, although most are the delta 509. Both parents must carry a CF related gene for an offspring to get it, and if so the risk is 25%. Carrier testing is available through specialty labs.If only one has trait ,zero.