Both newborns and adults can be tested for the
changed (mutated) gene that causes cystic fibrosis. These tests include:
Newborn screening. Levels of
a type of digestive enzyme are measured from a blood
sample. High levels of this enzyme suggest cystic fibrosis. Some newborns may also have
Genetic test for adults. These tests identify the most common defects in the
CFTR gene. Genetic testing can be
done during pregnancy through chorionic villus sampling or amniocentesis. The
test can also be done before pregnancy, to help couples find out if
either or both of them carry a defective CFTR gene.
If both parents
carry the changed gene, there is a 25% (1-in-4) chance that their child will
have no genetic problem. There is a 25% chance that their child will have cystic
fibrosis. And there is a 50% (1-in-2) chance that their child will be a
If only one
parent is a carrier of the changed gene, the child will not have cystic
fibrosis. But there is a 50% chance that the child will be a carrier.
This information is produced and provided by the National
Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National
Institute via the Internet web site at http://
.gov or call 1-800-4-CANCER.
WebMD Medical Reference from Healthwise
September 09, 2014
This information is not intended to replace the advice of a doctor.
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