Association of ACE gene I/D polymorphism with vitiligo: a meta-analysis

Associations of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) functional single-nucleotide polymorphisms (SNPs) with vitiligo have been reported, but the results were inconsistent. To investigate the association of SNPs in the intron 16 of ACE gene with vitiligo susceptibility by the meta-analysis, case-control studies were conducted by searching from PubMed, HighWire and China National Knowledge Infrastructure as of May 2011. A total of 6 studies with 828 patients and 1,215 controls was finally identified. All control samples were in Hardy-Weinberg equilibrium. According to the clinical typing, the data were divided into pooled subgroup and generalized subgroup. Our meta-analysis showed that a significantly increased vitiligo risk was associated with the D/D genotype compared with the I/I + I/D genotype (Odds ratio (OR) 1.79, 95% confidence interval (95% CI) 1.35-2.38, P < 0.0001) and the D allele compared with the I allele (OR 1.72, 95% CI 1.45-2.04, P < 0.00001) in pooled subgroup. In summary, this meta-analysis demonstrated that ACE D/D homozygote and D allele were significantly associated with an increased risk of vitiligo in pooled population. The results indicated that the people with ACE D/D homozygote and D allele may suffer from vitiligo, but of a generalized type. ACE polymorphism might be used as biomarkers for vitiligo risk prediction for pooled vitiligo.