HLA-DRB1 and leprosy: In both the Vietnamese and the Chinese populations, HLA-DQB1*04:01 is part of a haplotype which includes HLA-DQA1*03:03 and HLA-DRB1*04:05 (S1 Fig), and in a meta-analysis of studies in Chinese patients HLA-DQA1*03:03 was identified as main leprosy resistance factor [10].