Genetic Analysis of Ion Transport

Cystic fibrosis (CF) is an autosomal recessive disorder, and di Sant’ Agnese et al. [3] found that the sweat of CF patients contains an excess of sodium and chloride ions. Defects in the regulation of chloride ion transport have been documented in CF epithelial cells [5, 10, 14, 16]. The chloride channel normally responds to β-adrenergic agents, but CF cells are defective in this response [6, 9,14]. It has been proposed that the CF defect involves a pathway whereby cAMP regulates ion transport.