Association between CTLA-4 Exon-1 +49A>G Polymorphism and Primary Biliary Cirrhosis Risk: A Meta-analysis

Background and Aims exon-1 +49A>G polymorphisms have been reported to influence the risk for primary biliary cirrhosis in many studies; however, the results still remain controversial and ambiguous. The aim of this study was to determine more precise estimations for the relationship between CTLA-4 exon-1 +49A>G polymorphisms and the risk for primary biliary cirrhosis. s onic searches for all publications were conducted on associations between this variant and breast cancer in several databases through November 2010. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to estimate the strength of the association. Eight studies were identified including 2151 cases and 2214 controls. s l, there were no significant associations between CTLA +49G>A polymorphism and primary biliary cirrhosis risk (codominant model: GA vs. AA OR = 1.190, 95% CI = 0.818–1.732; GG vs. AA OR = 1.153, 95% CI = 0.858–1.550; dominant model: OR = 1.181, 95% CI = 0.873–1.599; and recessive model: OR = 1.148; 95% CI = 0.903–1.459). In the subgroup analysis by ethnicity, a significantly increased risk was found for Asians (GG vs. AA OR = 1.873; 95% CI = 1.202–2.921) and recessive model (OR = 1.758; 95% CI = 1.271–2.433). In the stratified analysis by control sources, significant association were observed in population-based studies (GA vs. AA OR = 1.432; 95% CI = 1.078–1.902). sions eta-analysis suggests that the CTLA-4 +49G>A polymorphism may be a risk factor for primary biliary cirrhosis in Asians.