AGT and atrial fibrillation: In AGT block 1, the diplotype with ‘GC’ was found AF risk (for two-copy, P = 0.036, OR = 1.450, 95% CI = 1.025–2.050); and the diplotype with ‘GT’ showed protective effects (for one-copy, P = 0.007, OR = 0.692, 95% CI = 0.528–0.906).