Evaluation of CTLA-4 Exon-1 +49A/G Polymorphism in Systemic Lupus Erythematosus Patients: A Meta Analysis

Cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) is an important negative regulator of T-cell responses. The49AG polymorphism of the CTLA-4 gene may be associated with systemic lupus erythematosus (SLE) risk، but the results from previous published studies have been inconsistent. We carried out a meta-analysis search to assess this association more precisely. A systematic search of six electronic databases (Pubmed، Science direct، OVID، Iran doc، Iran medex and SID: Scientefic Information Database) was performed for relevant articles published between 1978 and 2011. The odds ratio (OR) and its 95% confidence interval (95%CI) were used to assess the strength of the association. We evaluated both fixed and random effect models، depending on the presence of between-study heterogeneity. The data were analyzed using STATA software. A total of 15 independent studies on the CTLA-4 gene 49AG polymorphism and SLE، including 1705 cases and 2299 controls were used in the meta-analysis. No significant association was found between 49AG polymorphism and SLE risk in the overall or subgroup analyses. This meta-analysis showed no significant association between 49AG polymorphism and SLE susceptibility. Large-scale and well-designed case-control studies are suggested.