title: XRCC1 genetic polymorphism Arg399Gln and hepatocellular carcinoma risk: a meta-analysis.
abstract: BACKGROUND
  Studies investigating the association between X-ray repair cross-complementing group 1 (XRCC1) genetic polymorphism Arg399Gln and hepatocellular carcinoma (HCC) risk report conflicting results. The aim of this study was to quantitatively summarize the evidence for such a relationship.
  
  
  METHODS
  Two investigators independently searched the Medline, Embase, CNKI and Chinese Biomedicine Database. Summary odds ratios (ORs) and 95% confidence intervals (95% CIs) for XRCC1 polymorphism and HCC were calculated in a fixed-effects model (the Mantel-Haenszel method) and a random-effects model (the DerSimonian and Laird method) when appropriate. The pooled ORs were performed for a codominant model (Gln/Gln vs. Arg/Arg, Arg/Gln vs. Arg/Arg), a dominant model (Gln/Gln+Arg/Gln vs. Arg/Arg) and a recessive model (Gln/Gln vs. Arg/Gln+Arg/Arg).
  
  
  RESULTS
  This meta-analysis included 11 case-control studies, which included 2208 HCC cases and 3265 controls. Overall, the variant genotypes (Gln/Gln and Arg/Gln) of Arg399Gln were not associated with HCC risk when compared with the wild-type Arg/Arg homozygote (Gln/Gln vs. Arg/Arg, OR=1.01, 95% CI=0.79-1.28; Arg/Gln vs. Arg/Arg, OR=1.09, 95% CI=0.81-1.45). Similarly, no associations were found in the dominant and recessive models (dominant model, OR=1.12, 95% CI=0.85-1.47; recessive model, OR=0.99, 95% CI=0.79-1.25). Limiting the analysis to the studies within Hardy-Weinberg equilibrium, the results were persistent and robust. When stratifying for ethnicity, country/region and source of controls, no evidence of a significant association was observed in any subgroup. No publication bias was found in the present study.
  
  
  CONCLUSIONS
  No association is found between the XRCC1 polymorphism Arg399Gln and the risk of HCC.
authors.affiliation: Department of Liver and Vascular Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China.
authors.forename: Fei
authors.initials: F
authors.lastname: Liu
authors.forename: Bo
authors.initials: B
authors.lastname: Li
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Wei
authors.forename: Lvnan
authors.initials: L
authors.lastname: Yan
authors.forename: Tianfu
authors.initials: T
authors.lastname: Wen
authors.forename: Jichun
authors.initials: J
authors.lastname: Zhao
authors.forename: Mingqing
authors.initials: M
authors.lastname: Xu
mesh_terms: D006528:Carcinoma, Hepatocellular / Q000208:ethnology / Q000235:genetics*; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D004268:DNA-Binding Proteins / Q000235:genetics*; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D008113:Liver Neoplasms / Q000208:ethnology / Q000235:genetics*; D016015:Logistic Models; D016017:Odds Ratio; D010641:Phenotype; D011110:Polymorphism, Genetic; D018570:Risk Assessment; D012307:Risk Factors; D000076105:X-ray Repair Cross Complementing Protein 1
chemical_list: D004268:DNA-Binding Proteins; D000076105:X-ray Repair Cross Complementing Protein 1; C000619371:XRCC1 protein, human