CFTR and cystic fibrosis: Cystic Fibrosis (CF) is the most common fatal genetic disorder, caused by mutations in the Cystic Fibrosis Transmembrane Conductance Regulator (CFTR) gene (Kartner et al., 1991; Li et al., 1993; Riordan et al., 1989; Rommens et al., 1989).