HLA-DRB1 and vitiligo: To dissect the relative contributions of rs149554018, rs9271597, and the classical HLA alleles to vitiligo risk, we compared logistic regression models with haplotypes defined by different combinations of rs145954018, HLA-DRB1*13:01, rs9271597, HLA-DQA1*01:03, and HLA-DQB1*06:03.