<Tr> <Td_colspan="2"> (edit on Wikidata) </Td> </Tr> <P> Cystic fibrosis (CF) is a genetic disorder that affects mostly the lungs, but also the pancreas, liver, kidneys, and intestine . Long - term issues include difficulty breathing and coughing up mucus as a result of frequent lung infections . Other signs and symptoms may include sinus infections, poor growth, fatty stool, clubbing of the fingers and toes, and infertility in some males . Different people may have different degrees of symptoms . </P> <P> CF is inherited in an autosomal recessive manner . It is caused by the presence of mutations in both copies of the gene for the cystic fibrosis transmembrane conductance regulator (CFTR) protein . Those with a single working copy are carriers and otherwise mostly normal . CFTR is involved in production of sweat, digestive fluids, and mucus . When CFTR is not functional, secretions which are usually thin instead become thick . The condition is diagnosed by a sweat test and genetic testing . Screening of infants at birth takes place in some areas of the world . </P> <P> There is no known cure for cystic fibrosis . Lung infections are treated with antibiotics which may be given intravenously, inhaled, or by mouth . Sometimes, the antibiotic azithromycin is used long term . Inhaled hypertonic saline and salbutamol may also be useful . Lung transplantation may be an option if lung function continues to worsen . Pancreatic enzyme replacement and fat - soluble vitamin supplementation are important, especially in the young . Airway clearance techniques such as chest physiotherapy have some short - term benefit, but long - term effects are unclear . The average life expectancy is between 42 and 50 years in the developed world . Lung problems are responsible for death in 80% of people with cystic fibrosis . </P>

Where can the gene linked to cystic fibrosis be found