title: [Genetic polymorphisms in X-ray repair cross-complementing gene 1 and susceptibility to papillary thyroid carcinoma].
abstract: OBJECTIVE
  To study the association of polymorphisms in the X-ray repair cross-complementing gene 1 (XRCC1) and papillary thyroid carcinoma (PTC).
  
  
  METHODS
  A hospital based, matched case-control study was carried out. The polymorphisms in XRCC1 for 105 pairs of cases with PTC and controls were identified by PCR-RFLP.
  
  
  RESULTS
  The frequencies of Arg/Arg, Arg/Trp and Trp/Trp genotypes at XRCC1 Arg194Trp site were 47.6%, 49.5% and 2.9% among cases compared to 45.7%, 48.6% and 5.7% among controls. There was no statistically significant difference between the two groups (chi(2) = 1.07, P = 0.59). The frequencies of Arg/Arg, Arg/Gln and Gln/Gln genotypes at XRCC1 Arg399Gln site were 46.7%, 41.9% and 11.4% among cases, while 54.2%, 42.9% and 2.9% among controls respectively. There was statistically significant difference between the two groups (chi(2) = 6.40, P = 0.04). Individuals with Gln/Gln genotype had a 3.65-fold increased risk of developing PTC compared to Arg/Arg genotype (OR = 4.65, 95% CI: 1.24 - 17.45). The multivariate conditional logistic regression analysis showed that the XRCC1 Arg399Gln polymorphism, negative life events and X-irradiation history were associated with PTC, with odds ratios of 2.71 (95% CI: 1.22 - 6.05), 5.34 (95% CI: 1.40 - 20.38) and 0.38 (95% CI: 0.12 - 0.72) respectively. However, XRCC1 Arg194Trp polymorphism, drinking tea, fruit and economic levels did not show statistically significant associations with PTC.
  
  
  CONCLUSIONS
  The Gln/Gln genotype at XRCC1 Arg399Gln site and negative life events significantly increased while X-irradiation history decreased the risk of developing PTC.
authors.affiliation: Department of Epidemiology, School of Public Health, Fudan University, Shanghai 200032, China.
authors.forename: Qian-Xi
authors.initials: QX
authors.lastname: Zhu
authors.forename: Jian-Chao
authors.initials: JC
authors.lastname: Bian
authors.forename: Qiang
authors.initials: Q
authors.lastname: Shen
authors.forename: Feng
authors.initials: F
authors.lastname: Jiang
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Tang
authors.forename: Hong-Wei
authors.initials: HW
authors.lastname: Zhang
authors.forename: Yi
authors.initials: Y
authors.lastname: Wu
mesh_terms: D000328:Adult; D002291:Carcinoma, Papillary / Q000209:etiology / Q000235:genetics*; D016022:Case-Control Studies; D004260:DNA Repair / Q000235:genetics; D004273:DNA, Neoplasm / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic; D013964:Thyroid Neoplasms / Q000209:etiology / Q000235:genetics*; D000076105:X-ray Repair Cross Complementing Protein 1
chemical_list: D004273:DNA, Neoplasm; D004268:DNA-Binding Proteins; D000076105:X-ray Repair Cross Complementing Protein 1; C000619371:XRCC1 protein, human