Meta-analysis of TNF-α promoter-308A/G polymorphism and SLE susceptibility in Asian populations

The aim of this study was to summarize results on the association of tumor necrosis factor-alpha (TNF-alpha) promoter -308A/G polymorphism with systemic lupus erythematosus (SLE) susceptibility in Asian populations by using the meta-analysis. We searched all the publications about the association between TNF-alpha promoter -308A/G polymorphism and SLE in Asian populations from PubMed, Elsevier Science Direct, Chinese Biomedical Literature Database (CBM), Chinese National Knowledge Infrastructure (CNKI), and Wanfang (Chinese). Meta-analysis was performed for genotypes AA versus GG, GA versus GG, AA versus GG + GA, GA + AA versus GG, and A allele versus G allele in a fixed/random effect model. A total of 12 studies (1017 cases and 1086 controls) were included in the current meta-analysis (Chinese, Japanese, and Thai). When all groups were pooled, a significant association of A allele and increased SLE risk was found (OR = 1.44, 95%CI = 1.04-2.01, P = 0.03). When analyses were restricted to more ethnically homogeneous populations, similar result was found in Chinese population (OR = 1.59, 95%CI = 1.12-2.26, P = 0.009). But the association between TNF-alpha promoter -308 polymorphism and SLE was not observed when examining the contrast of G/A + A/A versus G/G, A/A versus A/G + G/G, A/A versus G/G, and G/A versus G/G. This meta-analysis demonstrates the association between TNF-alpha promoter -308A/G polymorphism and SLE in Asian populations, especially in Chinese population.