title: FAS and FASL gene polymorphisms are not associated with hepatitis B virus infection based on a case-control study in a Brazilian population.
abstract: OBJECTIVE
  This study investigated the association of the single nucleotide polymorphisms (SNPs) in the FAS and FASL genes with the outcome of hepatitis B virus (HBV) infection.
  
  
  METHODS
  Blood samples were collected from 116 HBV-infected patients at the Hospital of the Santa Casa de Misericordia Foundation (Belém, PA, Brazil). Seronegative individuals were used as controls. DNA samples were extracted from the leukocytes and assayed using the polymerase chain reaction (PCR) followed by RFLP analysis with restriction endonucleases.
  
  
  RESULTS
  The frequencies of the mutant genotypes for -670FAS (GG), Ivs2nt-124FASL (GG), Ivs3nt-169FASL (ΔT/ΔT), and -844FASL (TT) were higher in the HBV patients, and the FAS-1377AA genotype was more frequent in the control group; however, the differences between the allele and genotype frequencies were not statistically significant. When the HBV patient population was divided into two groups (inactive carriers and active chronic hepatitis patients), the mutant genotypes were found to be more prevalent in the active chronic hepatitis group with respect to the FAS gene polymorphisms; however, this difference was not statistically significant.
  
  
  CONCLUSIONS
  The results suggest that the polymorphisms in FAS and FASL genes are not associated with HBV infection or even with the natural history of the infection in the Brazilian Amazon region.
authors.affiliation: Laboratório de Virologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Guamá, 66075-110 Belém, PA, Brazil.
authors.forename: Bárbara B
authors.initials: BB
authors.lastname: Santana
authors.affiliation: Laboratório de Virologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Guamá, 66075-110 Belém, PA, Brazil.
authors.forename: Maria Luana C
authors.initials: ML
authors.lastname: Viégas
authors.affiliation: Fundação Santa Casa de Misericórdia do Pará, 66050-380 Belém, PA, Brazil.
authors.forename: Simone R S S
authors.initials: SR
authors.lastname: Conde
authors.affiliation: Laboratório de Virologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Guamá, 66075-110 Belém, PA, Brazil.
authors.forename: Marluísa O G
authors.initials: MO
authors.lastname: Ishak
authors.affiliation: Laboratório de Virologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Guamá, 66075-110 Belém, PA, Brazil.
authors.forename: Ricardo
authors.initials: R
authors.lastname: Ishak
authors.affiliation: Laboratório de Virologia, Instituto de Ciências Biológicas, Universidade Federal do Pará, Guamá, 66075-110 Belém, PA, Brazil.
authors.forename: Antonio C R
authors.initials: AC
authors.lastname: Vallinoto
mesh_terms: D001938:Brazil; D016022:Case-Control Studies; D053222:Fas Ligand Protein / Q000235:genetics*; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease; D019694:Hepatitis B, Chronic / Q000235:genetics*; D006801:Humans; D020641:Polymorphism, Single Nucleotide; D017422:Sequence Analysis, DNA; D019014:fas Receptor / Q000235:genetics*
chemical_list: C491901:FAS protein, human; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D019014:fas Receptor