ABO and duodenal ulcer: One of them reported only two SNPs (rs2294008 PSCA and rs505922 ABO) associated with duodenal ulcer in Japanese [44]; another determined eight PUD-associated loci in the MUC1, MUC6, FUT2, PSCA, ABO, CDX2, GAST and CCKBR genes, including the two reported for the Japanese cohort [45].