Search

Abstract: Background: Some studies suggested that Glutathione S-transferases M1/T1(GSTM1/T1) null polymorphisms may be associated with the risk of vitiligo. Aims: The purpose of this study is to further evaluate the association between GSTM1/T1 null polymorphisms and the susceptibility to vitiligo. Methods: We carried out a retrieval of studies in the databases. Odds ratios (OR) and 95% confidence intervals (95% CIs) were used to assess the strength of this association. We analyzed the data using Stata 11.0. Results: Six case–control studies including 1358 cases and 1673 controls were included in this meta-analysis. Our overall results showed the GSTM1 or GSTT1 null polymorphism was associated with vitiligo (GSTM1:OR=1.59, 95% CI: 1.21–2.08, P=0.001; GSTT1: OR=1.30, 95% CI: 1.12–1.51, P=0.001). In the subgroup analysis, the GSTM1 null polymorphism might be a genetic risk factor to vitiligo in East Asian (OR=1.71, 95% CI: 1.12–2.63, P=0.014) but not in the Mediterranean, however individuals with the GSTT1 null polymorphism in the Mediterranean (OR=1.76, 95% CI: 1.15–2.71, P=0.010) but not in East Asian have a greater predisposition to vitiligo. In addition there was also a significant trend toward an association with the combination of the GSTM1 null and GSTT1 null in either East Asians or Mediterraneans. Conclusion: The GSTM1/T1 null polymorphisms may be associated with vitiligo. More studies are needed to confirm this conclusion. [Copyright &y& Elsevier]

Background and Aims: Several studies have shown that the apolipoprotein E (ApoE) gene is associated with the development of psoriasis. However, there is a controversy. The aim of the present study was to evaluate the association of psoriasis risk with ApoE polymorphisms. Methods: We carried out a systematic search of studies that explored associations between ApoE polymorphisms and psoriasis. The genotype distribution of the control group in each study was calculated to determine whether or not there was compliance with the Hardy-Weinberg equilibrium. Overall effect sizes were assessed by odds ratio (OR) with 95% confidence intervals (CI). The selection to use the random-effects model or fixed-effects model depended on the size of the heterogeneity among the included studies. The fail-safe number (Nfs) was used to test the potential publication bias. We analyzed the data using Stata v.10.0. Results: A total of seven studies with 966 patients and 1,086 controls were included. The results indicated that the ε2 allele was associated with increased risk of psoriasis (ε2 vs. ε3+ε4: OR = 1.47, 95% CI = 1.23–1.75, p <0.05), whereas the ε3 allele and ε3/ε3 genotype may decrease risk of psoriasis (OR = 0.71, 95% CI = 0.62–0.82, p <0.05; OR = 0.63, 95% CI = 0.52–0.77, p <0.05, respectively). In the subgroup analysis according to ethnicity, the increased risk of psoriasis remained in the Asian and European populations, whereas no significant association was found in other populations for other polymorphisms. Conclusions: Our study suggests that the ApoE polymorphisms are associated with the risk of psoriasis, especially ε2 and ε3 alleles. Further studies are needed to confirm our results. [Copyright &y& Elsevier]