title: Association of TNF-α Gene Polymorphisms with Production of Protein and Susceptibility to Chronic Hepatitis B Infection in the South East Iranian Population.
abstract: BACKGROUND
  The host genetic background regulates the natural history of chronic hepatitis B virus (HBV) infection.
  
  
  OBJECTIVE
  The aim of this study was to investigate the association between TNF-α gene polymorphism in the promoter region and susceptibility to chronic hepatitis B virus infection.
  
  
  METHODS
  Four polymorphisms of TNF-α gene including -238 A/G, -308 A/G, -857 C/T, and -863 A/C were analyzed by PCR-RFLP in 100 chronic HBV infected patients (HBV group), 40 spontaneously recovered HBV subjects (SR group), and 100 healthy controls (C group). Also, serum levels of protein were monitored.
  
  
  RESULTS
  The study showed that the existence of -308 G, -857 C, and -863 A alleles signiﬁcantly increased susceptibility to chronic HBV infection. In addition, GGCA haplotype had a higher frequency in HBV patients than C and SR groups that might be related to the natural history of the infection. Chronic HBV patients with -308 GG, -857 CC, and -863 AA genotypes had lower serum levels of TNF-α compared to those with other genotypes.
  
  
  CONCLUSIONS
  The results indicated that there was a positive association between susceptibility to chronic HBV infection and TNF-α polymorphism. In addition, HBV patients carrying -308 GG, -857 CC, and -863 AA genotypes with lower serum levels of TNF-α had an increased risk of infection.
authors.affiliation: Infectious Diseases and Tropical Medicine Research Center, Zahedan University of Medical Sciences, Zahedan, Iran; Department of Histology, School of Medicine, Zahedan University of Medical Sciences, Zahedan, Iran.
authors.forename: Zahra
authors.initials: Z
authors.lastname: Heidari
authors.affiliation: Infectious Diseases and Tropical Medicine Research Center, Zahedan University of Medical Sciences, Zahedan, Iran; Department of Histology, School of Medicine, Zahedan University of Medical Sciences, Zahedan, Iran.
authors.forename: Bita
authors.initials: B
authors.lastname: Moudi
authors.affiliation: Infectious Diseases and Tropical Medicine Research Center, Zahedan University of Medical Sciences, Zahedan, Iran; Department of Histology, School of Medicine, Zahedan University of Medical Sciences, Zahedan, Iran.
authors.forename: Hamidreza
authors.initials: H
authors.lastname: Mahmoudzadeh Sagheb
authors.affiliation: Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran.
authors.forename: Mehrnoosh
authors.initials: M
authors.lastname: Moudi
keywords: Chronic Hepatitis B Virus; Gene; Polymorphism; Tumor Necrosis Factor-a