Meta-analysis of TNF-α promoter − 238A/G polymorphism and SLE susceptibility

Abstract

The tumor necrosis factor-α (TNF-α) promoter − 238A/G polymorphism has been repeatedly associated with systemic lupus erythematosus (SLE), but findings are not consistent across studies. Our aim was to do a meta-analysis to assess the association between TNF-α promoter − 238A/G polymorphism and SLE. Eleven published studies of this polymorphism with SLE in different ethnic groups were identified using a Medline search. 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. The overall odds ratio (OR) of the AA versus GG+GA genotypes was 3.46 (95% CI = 1.35–8.83, P = 0.01), and a similar result was found in Caucasian population (OR = 4.62, 95% CI = 1.20–17.80, P = 0.03); the overall OR of the AA versus GG genotypes was 3.36 (95% CI = 1.32–8.55, P = 0.01), and a similar result was found in Caucasian population (OR = 4.29, 95% CI = 1.11–16.53, P = 0.03); the OR of the GA versus GG genotypes was 0.48 (95% CI = 0.30–0.75, P = 0.001) in Caucasian population. In conclusion, this meta-analysis demonstrates the association between TNF-α promoter − 238A/G polymorphism and SLE, especially in Caucasian population.

Keywords::

• Meta-analysis
• TNF-α
• systemic lupus erythematosus
• genetic polymorphisms
• bias

Acknowledgments

We thank all the people who helped us in our study, including Drs Gabriel Tobón, Heiko Schotte, Juan-Manuel Anaya, Silvia Della Bella, Tim Vyse, Lorena Orozco, and especially Martin Rudwaleit, who sent us his original paper.

Declaration of interest: This work was supported by grants from the National Natural Science Foundation of China (30830089). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.