Cystic Fibrosis Carrier Screening

What Causes Cystic Fibrosis?

Cystic fibrosis is a genetic disorder. A child must inherit two defective CF genes (one defective gene from each parent) to have the disease.

A person who has inherited only one defective CF gene is a carrier of cystic fibrosis and does not have the disease but can pass it on to his or her children. This person can also pass on carrier status.

• If only one parent is a carrier of a defective CF gene, the child will not have CF. But there is a 50% (1-in-2) chance that the child will be a CF carrier.
• If both parents are carriers, there is a 25% (1-in-4) chance that the child will have CF, but a 50% chance that the child will be a carrier.

Go to previous section	Go to top of page	Go to next section
Author:	Debby Golonka, MPH	Last Updated: June 26, 2007
Medical Review:	Michael J. Sexton, MD - Pediatrics Susanna McColley, MD - Pediatric Pulmonology
© 1995-2008 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.This information does not replace the advice of a doctor. Healthwise disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.