PSCA and peptic ulcer disease: Using the UK biobank data, eight independent loci for peptic ulcer are revealed to be located at or near ABO, mucin (MUC)1, MUC6, fucosyltransferase 2 (FUT2), prostate stem cell antigen (PSCA), caudal type homeobox 2 (CDX2), gastrin (GAST), and cholecystokinin B receptor (CCKBR) genes.