Cystic Fibrosis Carrier Screening

This genetic test screens for 68 of the most common mutations in the CFTR gene, the gene responsible for cystic fibrosis. Cystic fibrosis is one of the most common inherited recessive conditions, and carrier screening identifies whether a person carries a CFTR mutation. It is commonly requested by couples planning a pregnancy, by people with a family history of cystic fibrosis, and in the investigation of certain fertility problems.

Cystic fibrosis is among the most common autosomal recessive genetic conditions in people of European ancestry. It is caused by mutations in the CFTR gene, which encodes a chloride channel important for the function of the lungs, pancreas, and other organs. A person who inherits two faulty copies of the gene is affected, while someone with a single faulty copy is an unaffected carrier who can pass the variant to their children. The laboratory's test analyses 68 of the most frequent CFTR mutations from a blood sample, covering the large majority of disease-causing variants seen in the population. Carrier screening is particularly valuable for couples planning a family: if both partners are carriers, each pregnancy carries a one-in-four chance of an affected child, and knowing this allows informed reproductive choices and access to prenatal or pre-implantation testing. CFTR testing is also relevant in the investigation of male infertility, as certain CFTR variants are associated with congenital absence of the vas deferens. Because the panel targets a defined set of mutations rather than sequencing the whole gene, a negative result substantially reduces but does not entirely eliminate carrier risk; results are interpreted in the context of family history and ancestry, and genetic counselling is recommended where a variant is found.