In conclusion, our findings support that the eQTL SNP at rs9264942 regulates HLA-C expression in the Japanese and suggest that the four SNPs, which are in strong linkage disequilibrium, may be surrogate marker candidates of a particular HLA haplotype, HLA-C*12:02~B*52:01~DRB1*15:02, related to IBD susceptibility and disease outcome. Here, HLA-DRB1 is linked to inflammatory bowel disease.