Cystic Fibrosis Carrier Screening

This test is designed to detect carriers of cystic fibrosis. Cystic fibrosis (CF) is an autosomal recessive disorder of variable severity that affects the pulmonary system, digestive system, and other organ systems. Clinical features of CF include progressive lung disease, pancreatic insufficiency, male infertility, and elevated sweat chloride levels. Severely affected individuals may require lung transplantation and have shortened life expectancies, primarily due to respiratory failure. Other individuals have milder symptoms, including some males in whom the only finding is infertility due to congenital absence of the vas deferens (CAVD). Cystic fibrosis (MIM 219700) and CAVD (MIM 277180) are caused by pathogenic variants in the CFTR gene (NM_000492). Individuals with a heterozygous pathogenic variant in CFTR are carriers for cystic fibrosis/CAVD and are at risk of having a child with the disorder. If both reproductive partners are cystic fibrosis carriers, the risk for cystic fibrosis in their children is 25%. Cystic fibrosis has a high incidence in non-Hispanic white populations (approximately 1 in 2500 individuals), and a lower prevalence in other ethnic groups. Approximately 70% of CF carriers in non-Hispanic white populations carry the p.Phe508del (deltaF508) pathogenic variant. The American College of Obstetrics and Gynecology (ACOG) recommends offering cystic fibrosis carrier screening to all women who are pregnant or considering pregnancy. This test is intended for pre/post-conception carrier screening and is not intended for diagnostic testing.