Human leukocyte antigen (HLA)-DRB1 allele polymorphisms and systemic sclerosis.

Human leukocyteantigen (HLA) is the most important gene for immune system regulation. Although studies have evaluated the association between HLA-DRB1 allele polymorphisms and systemic sclerosis (SSc), their results are still controversial. We performed a meta-analysis to assess the association of HLA-DRB1 alleles with risk of SSc. Electronic database were systematically searched for articles, a total of 11 case-control studies including 3268 cases and 5548 controls were analyzed. Odds ratio (ORs) and 95% confidence intervals were used to assess the association of HLA-DRB1 alleles with SSc. The relationship between SSc-related autoantibodies and DRB1 alleles was also analyzed. In the overall analysis, four alleles (DRB104:03, DRB108, DRB111, and DRB111:04) increased the risk of SSc; however, five alleles (DRB107, DRB111:01, DRB113, DRB113:01, and DRB114) had the opposite effect. Analysis of subgroups by ethnicity indicate that DRB111:01 and DRB113:01 confer a protective effect in Caucasians, while DRB111:04 was associated with a higher risk of SSc. For Asian, DRB113:02 was found to be a protective factor. In addition, the frequency of DRB111:04 alleles was significantly increased in ATA SSc patients compared with ATA SSc patients. DRB104:03, DRB108, DRB111, and DRB111:04 were associated with the risk of SSc. Additionally, DRB111 and DRB111:04 were association with ATAs.