Major advances have been made during the past 4 years in understanding the pathophysiology of aldosterone production in patients with primary aldosteronism (PA). The breakthrough was the identification of somatic mutations in the potassium channel GIRK4 (encoded by KCNJ5) in aldosterone-producing adenomas (APAs) and the contemporaneous discovery, by the same authors, of a germline mutation responsible for familial hyperaldosteronism type III.2 This was followed by the identification of further somatic mutations in APAs in 2 ATPases (Na+/K+-ATPase 1 and Ca2+-ATPase 3, encoded by ATP1A1 and ATP2B3, respectively) and in a subunit of an L-type voltage-gated Ca2+-channel, Cav1.3 (encoded by CACNA1D).
