What Your Test Results Mean:

Carriers typically show no symptoms of cystic fibrosis; however, carriers are at an increased risk of having a child with cystic fibrosis. Risk for the current or future pregnancies is dependent on your partner’s carrier status.

Disease Explained:

Cystic fibrosis is an inherited condition that affects the lungs, pancreas, liver, and male reproductive system. Some males may not develop lung or gastrointestinal symptoms of the disease and will only present with male infertility caused by congenital absence of the vas deferens (CAVD). Both cystic fibrosis and CAVD are caused by abnormalities in the cystic fibrosis transmembrane conductance regulator (CFTR). Individuals with cystic fibrosis are unable to properly regulate epithelial chloride and sodium channels, leading to an increased risk for lung infections, digestion problems, diarrhea, poor growth and male infertility.

Management of disease is lifelong to prevent pulmonary complications and enhance weight gain. The majority of individuals with cystic fibrosis will require oral pancreatic enzyme replacement. With advances in treatment and appropriate management, individuals with cystic fibrosis typically live into their late thirties. Individuals with CAVD may conceive children through assisted reproductive technologies.

How the Genetics Works:

The clinical features of cystic fibrosis disease can be explained by pathogenic variants in the CFTR gene. In general, individuals have two copies of the CFTR gene. Carriers of cystic fibrosis disease have a single variant in one copy of the CFTR gene while individuals with cystic fibrosis disease have variants in both copies of their genes, one inherited from each parent.

Cystic Fibrosis Carrier Screening Test

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Heim et al. (2001). Improved detection of cystic fibrosis mutations in the heterogeneous U.S. population using an expanded, pan-ethnic mutation panel. Genet Med, 3(3):168-176.
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Monaghan et al (2004). Preconception and prenatal cystic fibrosis carrier screening of African American reveals unanticipated frequencies for specific mutations. Genet Med 6(3):141-144.
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Perez et al. (2007). CFTR gene analysis in Latin American CF patients: Heterogeneous origin and distribution of mutations across the continent. J Cystic Fibrosis, 6:194-208.
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Sugarman et al. (2004). CFTR mutation distribution among U.S. Hispanic and African American individuals: Evaluation in cystic fibrosis patient and carrier screening populations. Genet Med, 6(5):392-399.
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Additional Cystic Fibrosis References: Available upon request