The CFTR gene (Cystic Fibrosis Transmembrane Conductance Regulator) provides instructions for making a protein that functions as a channel across the membrane of cells that produce mucus, sweat, saliva, tears, and digestive enzymes. This channel transports negatively charged particles called chloride ions into and out of cells, which helps control the movement of water in tissues, necessary for the production of thin, freely flowing mucus.
