Cystic fibrosis (CF) arises from the mutation of a gene encoding the functional protein, cystic fibrosis transmembrane conductance regulator (CFTR) which is involved in the production of sweat, digestive fluids, and mucus.[1] The CFTR protein plays important role in mucosal surfaces, and its dysfunction usually gives rise to thicker secretion of glands, therefore results in obstruction of exocrine glands all over the body. The gene discussed is CFTR; the disease is cystic fibrosis.