CFTR and cystic fibrosis: This non-cystic fibrosis transmembrane conductance regulator (CFTR)-mediated, alternative chloride current has been discussed as an important modulator of disease and therapeutic target in CF patients (Berschneider et al. 1988; Bronsveld et al. 2000; Taylor et al. 1988; Willumsen and Boucher 1989).