Thick, sticky mucus builds up in the lungs and pancreas of people with cystic fibrosis. The disorder is caused by mutations in the CFTR gene on chromosome 7. The protein normally functions as a chloride channel; defective channels disrupt salt and water movement across cell membranes.

Inheritance is autosomal recessive. Carriers are healthy, but two carrier parents have a 25 percent chance of an affected child. Symptoms include chronic lung infections, pancreatic insufficiency, and elevated sweat chloride. Newborn screening and genetic testing enable early diagnosis.

Treatment focuses on airway clearance, antibiotics, nutritional support, and CFTR modulator drugs that improve protein function for certain mutations. Median survival has increased dramatically with modern care. Research continues on gene therapy and further modulator combinations.

• Autosomal recessive disorder of the CFTR gene
• Affects lungs, pancreas, and other organs
• Causes thick mucus and chronic infections
• Managed with modulators and supportive care