Cystic fibrosis is a common autosomal recessive disorder that affects many functions of the body such as respiration, endocrine function, and reproduction. Although great strides in treatment have increased the length and quality of life for CF patients, it is nearly always fatal by the fourth decade of life. Sweat chloride testing remains the gold standard for diagnosis of CF, however DNA analysis is indicated not only for CF patients but also for their extended families. In addition to providing information about the specific mutations that cause CF, molecular testing allows rapid detection of cystic fibrosis carriers and can determine if the patient has a pancreatic sufficient or insufficient type of the disease. This information plays a large role in clinical management of the affected individual. Over 2000 variants have been reported in the CFTR gene. The carrier rates of the disorder are 1/25 Caucasians, 1/60 African-Americans, 1/46 Hispanics, 1/90 Asians, and 1/29 in the Ashkenazi Jewish population.