CPT® Code 81222

CFTR (cystic fibrosis transmembrane conductance regulator) (eg, cystic fibrosis) gene analysis; duplication/deletion variants

The CPT® Code 81222 pertains to the molecular genetic testing of the CFTR (cystic fibrosis transmembrane conductance regulator) gene, specifically focusing on the analysis of duplication and deletion variants. This gene, located on chromosome 7, is crucial for encoding the CFTR protein, which 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 the characteristic symptoms of cystic fibrosis (CF). 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 cystic fibrosis can be influenced by whether the mutations are heterozygous (one mutated gene) or homozygous (two mutated genes). For instance, the homozygous pairing of the del508F mutation is associated with more severe disease manifestations. The disease significantly impacts pulmonary function, with respiratory infections being a leading cause of morbidity and mortality, often culminating in respiratory failure. Additionally, pancreatic insufficiency occurs in approximately 85% of cases, leading to digestive complications. Other associated conditions may include sinusitis, nasal polyps, liver disease, and pancreatitis. The life expectancy for individuals with cystic fibrosis, even those with milder forms, averages around 30 years. The CPT® Code 81222 specifically addresses the identification of duplication and deletion variants of the CFTR gene, which are critical for understanding the genetic basis of cystic fibrosis. This analysis complements other genetic tests, such as those for common CFTR variants (CPT® Code 81220) and known familial variants (CPT® Code 81221), providing a comprehensive approach to genetic testing in individuals suspected of having cystic fibrosis or those with a family history of the disease.