CFTR and cystic fibrosis: Cystic fibrosis (CF) is a prevalent geneticdisorder caused bymutations in the cystic fibrosis transmembrane conductance regulator(CFTR) protein, a cyclic adenosine monophosphate(cAMP)-dependent anion channel that conducts chloride and bicarbonateacross epithelial apical membranes of multiple exocrine organs.