Objective: The interleukin-10 (IL-10) gene polymorphism (-1082A/G) has been shown to be associated with systemic lupus erythematosus (SLE), but findings are not consistent across studies. The aim of our meta-analysis was to assess the association between the -1082A/G polymorphism in the IL-10 gene and SLE.
Methods: We searched all publications on the association between the IL-10 (-1082A/G) polymorphism and SLE in PubMed, Elsevier Science Direct, Chinese Biomedical Literature Database (CBM), Chinese National Knowledge Infrastructure (CNKI) and Wanfang (Chinese). Meta-analysis was conducted using software Stata version 10.1. Meta-odds ratios (ORs) and 95% confidence intervals (CIs) based on fixed-/random-effects models depended on Cochran's Q-statistic and I(2) values.
Results: A total of 17 studies with 2396 cases and 3653 controls were included in this meta-analysis. Meta-analysis was performed for genotypes GG versus AA, GG + AG versus AA, GG versus AG + AA, and G allele versus A allele. Significant differences were found in genotype distribution between SLE and normal controls in whole-population GG versus AA (OR = 1.428, 95% CI = 1.006-2.208). Similar results were detected in the dominant genetics effect of the G allele (OR = 1.202, 95% CI = 1.030-1.403). No significant association was found in allele distribution in whole-population G versus A (OR = 1.125, 95% CI = 0.998-1.269). In subgroup analysis by ethnicity, significant association was found when GG + AG versus AA was performed in a European population (OR = 1.240, 95% CI = 1.022-1.503) and GG versus AG + AA was performed in an Asian population (OR = 3.596, 95% CI = 1.389-9.311). Significant association was found between genotype distribution in Asians (OR = 4.491, 95% CI = 1.552-13.000). Publication year was detected as the source of heterogeneity. In the stratified analysis by publication year, the pooled OR was 1.049 (95% CI = 0.940-1.171; P (heterogeneity) = 0.431; I(2) ( )= 0.4%) in subgroup 1 (publication years 1999-2004). No significant association was found between the IL-10 (-1082 G) allele and SLE in subgroup 1 (Z = 0.85, p = 0.431). In subgroup 2 (publication years 2005-2011), the pooled OR was 1.327 (95% CI = 1.125-1.565; P (heterogeneity) = 0.143; I(2) ( )= 35.8%). Significant association was found between the IL-10 (-1082 G) allele and SLE (Z = 3.36, p = 0.001).
Conclusions: This meta-analysis demonstrates the association between the IL-10 (-1082A/G) polymorphism and SLE. However, further studies are needed for a definitive conclusion.