AF is more prevalent in patients with PA (7.3%) vs. matched patients with essential hypertension (0.6%)29, adrenalectomy lowers the PA-associated risk of AF30 and the MR-specific antagonist eplerenone is associated with a 42% relative risk reduction of AF,31 all suggesting a potential role of aldosterone in the pathogenesis of AF independent of upstream regulatory hormones (i.e. renin/angiotensin-II). The gene discussed is AGT; the disease is atrial fibrillation.