title: DNA repair gene XRCC1 polymorphisms and susceptibility to childhood acute lymphoblastic leukemia: a meta-analysis.
abstract: OBJECTIVE
  To estimate the relationship between genetic polymorphisms of X-ray repair cross-complementing group 1 (XRCC1) and the susceptibility to childhood acute lymphoblastic leukemia (ALL).
  
  
  METHODS
  Relevant case-control studies were enrolled in the meta-analysis. We applied Rev Man 4.2 software to pool raw data and test studies' heterogeneity and to calculate the incorporated odds ratio (OR) and 95% confidence interval (95% CI).
  
  
  RESULTS
  Our data showed that the OR for the Gln allele of the Arg399Gln polymorphism, compared with the Arg allele, was 1.35 (95% CI, 1.16-1.57; P<0.0001) for childhood ALL patients. Similarly, the homozygous genotype Gln/Gln and heterozygous genotype Arg/Gln both significantly increased the risk of childhood ALL compared with the wild genotype Arg/Arg (OR =1.58; 95% CI, 1.13-2.21; P=0.008; OR =1.51; 95% CI, 1.21-1.87; P=0.0002). The dominant model of Arg399Gln was associated with childhood ALL risk (OR =1.54; 95% CI, 1.25-1.89; P<0.0001). The ethnic subgroup analysis demonstrated that the Gln allele in all five ethnic groups was prone to be a risk factor for childhood ALL just with different degrees of correlation while Arg194Trp SNP showed a protective or risk factor or irrelevant thing in different races.
  
  
  CONCLUSIONS
  XRCC1 399 polymorphism may increase the risk of childhood ALL. Different ethnic groups with some gene polymorphism have different disease risks.
authors.affiliation: Department of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China.
authors.forename: Juan
authors.initials: J
authors.lastname: Du
authors.forename: Cong
authors.initials: C
authors.lastname: Lu
authors.forename: Guohui
authors.initials: G
authors.lastname: Cui
authors.forename: Yan
authors.initials: Y
authors.lastname: Chen
authors.forename: Jing
authors.initials: J
authors.lastname: He
keywords: X-ray repair cross-complementing group 1 (XRCC1); acute lymphoblastic leukemia (ALL); childhood; gene polymorphism