title: Association of -238G/A polymorphism of tumor necrosis factor-alpha gene promoter region with outcomes of hepatitis B virus infection in Chinese Han population.
abstract: OBJECTIVE
  To clarify whether -238G/A polymorphism of tumor necrosis factor-alpha (TNF-alpha) gene promoter region was associated with outcomes of hepatitis B virus (HBV) infection in Han population of northern China, and to analyze the gene-environment interaction between -238G/A polymorphism and cigarette smoking or alcohol consumption.
  
  
  METHODS
  A case-control study was conducted to analyze the association of TNF-alpha gene promoter polymorphism with HBV infection outcomes. A total of 207 patients with chronic hepatitis B (HB) and 148 cases of self-limited HBV infection from Ditan Hospital and Shunyi District Hospital in Beijing, respectively were recruited. History of smoking and alcohol drinking was inquired by a questionnaire. The -238G/A polymorphism of TNF-alpha gene promoter was genotyped by polymerase chain reaction-restricted fragment length polymorphism (PCR-RFLP).
  
  
  RESULTS
  The frequencies of GG and GA genotypes were 98.07% and 1.93% in chronic HB patients and 93.24% and 6.76% in self-limited HBV infection individuals, respectively (chi(2)=5.30, P=0.02). The frequency of G allele was significantly higher in patients with chronic HB that in individuals with self-limited HBV infection (99.03% vs 96.62%, chi(2)=5.20, P=0.02). Only modestly increased risk of onset of chronic HB was found in smokers (OR=1.40, 95% CI: 0.87-2.28, P=0.14) and drinkers (OR=1.26, 95%CI: 0.78-2.05, P=0.32). There was a positive interaction between genotype GG and cigarette smoking with an interaction index (II) of 2.95, or alcohol consumption with an II of 1.64.
  
  
  CONCLUSIONS
  The -238G/A polymorphism of TNF-alpha gene promoter region is independently associated with different outcomes of HBV infection.
authors.affiliation: Department of Epidemiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences; School of Basic Medicine, Peking Union Medical College, 5 Dongdan 3 Tiao, Beijing 100005, China.
authors.forename: Liang-Ping
authors.initials: LP
authors.lastname: Lu
authors.forename: Xing-Wang
authors.initials: XW
authors.lastname: Li
authors.forename: Ying
authors.initials: Y
authors.lastname: Liu
authors.forename: Guo-Chang
authors.initials: GC
authors.lastname: Sun
authors.forename: Xue-Ping
authors.initials: XP
authors.lastname: Wang
authors.forename: Xi-Lin
authors.initials: XL
authors.lastname: Zhu
authors.forename: Quan-You
authors.initials: QY
authors.lastname: Hu
authors.forename: Hui
authors.initials: H
authors.lastname: Li
mesh_terms: D044466:Asian People / Q000235:genetics*; D016022:Case-Control Studies; D004777:Environment; D020022:Genetic Predisposition to Disease / Q000453:epidemiology; D005838:Genotype; D019694:Hepatitis B, Chronic / Q000208:ethnology* / Q000235:genetics*; D006801:Humans; D011110:Polymorphism, Genetic; D011401:Promoter Regions, Genetic / Q000235:genetics; D012307:Risk Factors; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
chemical_list: D014409:Tumor Necrosis Factor-alpha