Single nucleotide polymorphism markers for low-dose aspirin-associated peptic ulcer and ulcer bleeding.

BACKGROUND AND AIM In our previous study, the SLCO1B1 521TT genotype and the SLCO1B1*1b haplotype were significantly associated with the risk of peptic ulcer in patients taking low-dose aspirin (LDA). The aim of the present study was to investigate pharmacogenomic profile of LDA-induced peptic ulcer and ulcer bleeding. METHODS Patients taking 100 mg of enteric-coated aspirin for cardiovascular diseases and with a peptic ulcer or ulcer bleeding and patients who also participated in endoscopic surveillance were studied. Genome-wide analysis of single nucleotide polymorphisms (SNPs) was performed using the Affymetrix DME Plus Premier Pack. SLCO1B1*1b haplotype and candidate genotypes of genes associated with ulcer bleeding or small bowel bleeding identified by genome-wide analysis were determined using TaqMan SNP Genotyping Assay kits, polymerase chain reaction-restriction fragment length polymorphism, and direct sequencing. RESULTS Of 593 patients enrolled, 111 patients had a peptic ulcer and 45 had ulcer bleeding. The frequencies of the SLCO1B1*1b haplotype and CHST2 2082 T allele were significantly greater in patients with peptic ulcer and ulcer bleeding compared to the controls. After adjustment for significant factors, the SLCO1B1*1b haplotype was associated with peptic ulcer (OR 2.20, 95% CI 1.24-3.89) and CHST2 2082 T allele with ulcer bleeding (2.57, 1.07-6.17). CONCLUSION The CHST2 2082 T allele as well as SLCO1B1*1b haplotype may identify patients at increased risk for aspirin-induced peptic ulcer or ulcer bleeding.