The inherited progressive disorder cystic fibrosis (CF) causes severe damage to the lungs, and other tissues in the body by affecting the cells that produce mucus, sweat, and digestive juices. In individuals carrying mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which encodes an ion channel controlling the flow of ions and water in and out of cells, the mucus in airways and other passageways, which normally is thin and slippery, becomes sticky and thick – thus instead of acting as a lubricant, it becomes a congestant.
