Association of vitiligo with HLA-A2: a meta-analysis

Linkage and association studies suggest that the human leucocyte antigen (HLA) region may be involved in the genetic susceptibility of vitiligo. HLA-A2 has been reported to be associated with vitiligo in some, but not all, studies.

To identify sources of the heterogeneity among studies and to quantify effect estimates, we examined the association of HLA-A2 with vitiligo in a meta-analysis of all observational studies comparing the frequencies of HLA-A2 between vitiligo individuals and controls during 1966-2005.

The summary odds ratio (OR) was calculated by using a fixed- or a random-effects model. Meta-regression analysis was undertaken to investigate the effects of study characteristics on the pooled OR.

Eleven case-controlled studies fulfilled our inclusion criteria. The studies identified a total of 777 patients and 4820 controls. Meta-analysis showed a significantly increased frequency of HLA-A2 in vitiligo among cases [OR = 2.07, 95% confidence interval (CI) 1.67-2.58]. Heterogeneity was explained by the quality of the study and the ethnic background of the participants. Meta-regression analysis further showed that the percentage of familial vitiligo among the subjects had a significant effect on the pooled OR (P = 0.008). No study had a significant effect on the pooled OR and no publication bias presented in the studies analysed (P = 0.688).

These findings strongly suggest an association between HLA-A2 and vitiligo.