The CTLA-4 +49 A/G, CT60 A/G and PTPN22 1858 C/T polymorphisms and susceptibility to vitiligo: a meta-analysis

The aim of this study was to explore whether cytotoxic T lymphocyte antigen-4 (CTLA-4) +49 A/G, CT60 A/G, and protein tyrosine phosphatase nonreceptor 22 (PTPN22) 1858 C/T polymorphisms confer susceptibility to vitiligo. A meta-analysis was conducted of the associations between the CTLA-4 +49 A/G, CT60 and PTPN22 1858 C/T polymorphisms and vitiligo using; (1) allele contrast, (2) the recessive model, (3) the dominant model, and (4) the additive model. A total of 14 separate comparisons were considered in our meta-analysis consisting of 3,404 patients with vitiligo and 5,069 controls (nine studies with 1,252 cases and 2,152 controls for the CTLA-4 polymorphisms and five studies with 1,800 cases and 3,269 controls for the PTPN22 polymorphism). Meta-analysis showed no association between vitiligo and the CTLA-4 +49 A/G polymorphism in all study subjects (OR of the G allele = 1.186, 95 % CI = 0.893-1.575, p = 0.240) and in European (OR = 1.016, 95 % CI = 0.873-1.182, p = 0.838). However, meta-analysis of the CTLA-4 CT60 A/G polymorphism showed an association between vitiligo and the CTLA-4 CT60 G allele in all study subjects (OR = 1.267, 95 % CI = 1.110-1.447, p = 4.5 x 10(-5)) and in the European group (OR = 1.345, 95 % CI = 1.163-1.556, p = 6.3 x 10(-6)). Analysis using the recessive model and homozygote contrast showed the same pattern for the CTLA-4 CT60 G allele. Meta-analysis of the PTPN22 1858 C/T polymorphism showed an association between the PTPN22 T allele and vitiligo in all subjects (OR = 1.507, 95 % CI = 1.320-1.720, p < 1.0 x 10(-8)) and in European group (OR = 1.530, 95 % CI = 1.339-1.748, p < 1.0 x 10(-8)), but not in Asians (OR = 0.482, 95 % CI = 0.152-1.530, p = 0.216). Analysis using the recessive, dominant model, and homozygote contrast showed the same pattern for the PTPN22 T allele. This meta-analysis demonstrates that the CTLA-4 CT60 A/G polymorphism confers susceptibility to vitiligo in Europeans, but no association was found between the CTLA-4 +49 A/G polymorphism and vitiligo susceptibility. The PTPN22 C1858T polymorphism is associated with vitiligo susceptibility in European population.