APOE and gastritis: We found a positive and significant genetic correlation (rg) of AD (excluding APOE region) with GERD (rg = 0.25, P = 8.19 × 10−18), PUD (rg = 0.28, P = 3.70 × 10−7), PGM (rg = 0.22, P = 2.38 × 10−14), gastritis-duodenitis (rg = 0.24, P = 2.40 × 10−8), IBS (rg = 0.19, P = 1.10 × 10−4), and diverticular disease (rg = 0.15, P = 2.97 × 10−5).