CPT® Code 81220

CFTR (cystic fibrosis transmembrane conductance regulator) (eg, cystic fibrosis) gene analysis; common variants (eg, ACMG/ACOG guidelines)

The CPT® Code 81220 pertains to the molecular genetic testing of the CFTR (cystic fibrosis transmembrane conductance regulator) gene, which is crucial for diagnosing cystic fibrosis. This gene is located on chromosome 7 and encodes a protein that functions as a chloride channel in epithelial cells. These cells are found in various organs, including the lungs, liver, pancreas, digestive tract, reproductive organs, and sweat glands. Mutations in the CFTR gene disrupt the normal movement of salt and water across cell membranes, leading to the production of thick, sticky mucus. This mucus can obstruct airways and glands, resulting in severe respiratory and digestive issues characteristic of cystic fibrosis. Cystic fibrosis is one of the most prevalent autosomal recessive disorders, particularly among Caucasians and Ashkenazi Jewish populations. Individuals who inherit a mutated CFTR gene from both parents may exhibit a range of symptoms, from mild to severe, while those inheriting a mutation from only one parent become carriers without showing symptoms. The severity of the disease can be influenced by whether the mutations are heterozygous (different mutations from each parent) or homozygous (the same mutation from both parents). The most common mutation, del508F, accounts for approximately 70% of CFTR mutations across populations and involves a deletion of three nucleotides, resulting in the loss of the amino acid phenylalanine at position 508 of the protein. Other notable mutations vary by population, with specific variants identified in Non-Hispanic Caucasians, Ashkenazi Jews, African Americans, and Hispanics. The implications of these mutations are significant, as they can lead to various complications, including severe pulmonary disease, pancreatic insufficiency, sinusitis, liver disease, and pancreatitis. The prognosis for individuals with cystic fibrosis is heavily influenced by respiratory health, with many facing respiratory failure due to recurrent infections. The life expectancy for individuals with even mild forms of the disease averages around 30 years. The gene analysis performed under CPT® Code 81220 focuses on identifying these common variants to aid in the diagnosis and management of cystic fibrosis.