title: The effect of CTLA-4 A49G polymorphism on rheumatoid arthritis risk: a meta-analysis.
abstract: BACKGROUND
  Recently, a number of studies have been performed to explore the association between CTLA-4 A49G polymorphism and rheumatoid arthritis (RA). However, the results of previous works are still controversial and ambiguous.
  
  
  METHODS
  In this work, we attempted to perform an updated meta-analysis of available case-control study in order to assess the association between CTLA-4 A49G polymorphism and RA risk. We searched the various citation databases without limits on languages. Article searching was performed by screening the references of retrieved studies manually. Odds ratios (OR) and 95% confidence intervals (95% CI) were calculated to evaluate the strength of the association.
  
  
  RESULTS
  We totally compiled 27 studies in 24 articles (9805 RA patients and 10691 control subjects) into our meta-analysis work. We found significant association between CTL-A4 A49G polymorphism and RA risk (GG vs. AA: OR = 1.13, 95% CI = 1.03-1.23; GA vs. AA: OR = 1.19, 95% CI = 1.07-1.33; GA + GG vs. AA: OR = 1.18, 95% CI = 1.07-1.29). In the subgroup analysis by ethnicity, evidences of significantly increased risk was also found in both Asian (GG vs. AA: OR = 1.34, 95% CI = 1.15-1.55; GA + GG vs. AA: OR = 1.24, 95% CI = 1.08-1.41) and Caucasian population (GA vs. AA: OR = 1.19, 95% CI = 1.03-1.37; GA + GG vs. AA: OR = 1.14, 95% CI = 1.01-1.29). No evidence of publication bias was found in this work.
  
  
  CONCLUSIONS
  Our meta-analysis suggests that CTLA-4 A49G polymorphism was associated with RA risk.
  The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/13000_2014_157.
authors.forename: Gang
authors.initials: G
authors.lastname: Li
authors.affiliation: Department of Orthopaedics, Daqing General Hospital Group Oilfield General Hospital, Daqing 163001, China. junfeng_shi001@163.com.
authors.forename: Fengjun
authors.initials: F
authors.lastname: Shi
authors.forename: Jingchen
authors.initials: J
authors.lastname: Liu
authors.forename: Ye
authors.initials: Y
authors.lastname: Li
mesh_terms: D001172:Arthritis, Rheumatoid / Q000235:genetics*; D044466:Asian People / Q000235:genetics / Q000706:statistics & numerical data; D060908:CTLA-4 Antigen / Q000235:genetics*; D016022:Case-Control Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D044465:White People / Q000235:genetics / Q000706:statistics & numerical data
chemical_list: D060908:CTLA-4 Antigen; C556706:CTLA4 protein, human