title: Genetic Polymorphisms of CYP2E1, GSTP1, NQO1 and MPO and the Risk of Nasopharyngeal Carcinoma in a Han Chinese Population of Southern China.
abstract: BACKGROUND
  Southern China is a major area for endemic nasopharyngeal carcinoma (NPC). Genetic factors as well as environmental factors play a role in development of NPC. To investigate the roles of previously described carcinogen metabolism gene variants for NPC susceptibility in a Han Chinese population, we conducted a case-control study in two independent study population groups afflicted with NPC in Guangdong and Guangxi Provinces of southern China.
  
  
  METHODS
  Five single nucleotide polymorphisms (SNPs) of CYP2E1-rs2031920, CYP2E1-rs6413432, GSTP1-rs947894, MPO-rs2333227 and NQO1-rs1800566 were genotyped by PCR-based RFLP, sequencing and TaqMan assay in 358 NPC cases and 629 controls (phase I cohort). Logistic regression analysis was used to estimate odds ratios (OR) and 95% confidence intervals (CI). To confirm our results, sixteen tag SNPs for GSTP1, MPO, NQO1 (which 100% covered these genes), and 4 functional SNPs of CYP2E1 were genotyped in another cohort of 213 NPC cases and 230 controls (phase II cohort).
  
  
  RESULTS
  No significant associations in NPC risk were observed for the five polymorphisms tested in the phase I cohort. In an additional stratified analysis for phase I, there was no significant association between cases and controls in NPC high risk population (EBV/IgA/VCA positive population). Analysis of 14 tagging SNPs within the same genes in an independent phase II cohort were in agreement with no SNPs significantly associated with NPC.
  
  
  CONCLUSIONS
  Our results suggest that polymorphism of CYP2E1, GSTP1, MPO and NQO1 genes does not contribute to overall NPC risk in a Han Chinese in southern China.
authors.affiliation: State Key Laboratory for Infectious Diseases Prevention and Control, Institute for Viral Disease Control and Prevention, Chinese Centers for Disease Control and Prevention, Beijing, China. ivp0@cdc.gov.
authors.forename: Xiuchan
authors.initials: X
authors.lastname: Guo
authors.forename: Yi
authors.initials: Y
authors.lastname: Zeng
authors.forename: Hong
authors.initials: H
authors.lastname: Deng
authors.forename: Jian
authors.initials: J
authors.lastname: Liao
authors.forename: Yuming
authors.initials: Y
authors.lastname: Zheng
authors.forename: Ji
authors.initials: J
authors.lastname: Li
authors.forename: Bailey
authors.initials: B
authors.lastname: Kessing
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: O'Brien