title: HLA-DP and γ-interferon receptor-2 gene variants and their association with viral hepatitis activity in chronic hepatitis B infection.
abstract: OBJECTIVE
  Studies show that polymorphisms in human leukocyte antigen (HLA)-DP loci and certain γ-interferon (IFN-γ) signaling pathway genes are related to persistence of hepatitis B virus (HBV) infection and viral load in chronic HBV (CHB) infection respectively. Our study aims to determine whether single-nucleotide polymorphisms (SNPs) linked to HLA-DP loci and IFN-γ signaling pathway are associated with HBV activities.
  
  
  METHODS
  We compared the SNPs in the HLA-DPA1 gene (rs3077) and the IFN-γ receptor-2 gene (rs2284553 and rs9808753) of 100 treatment-naive hepatitis B e antigen (HBeAg)-negative CHB patients with undetectable HBV DNA with 100 age- and sex-matched controls with HBV DNA > 2000 IU/mL.
  
  
  RESULTS
  The median age of the study group was 47.9 years, and 61% were male patients. The distribution of the three polymorphisms was in Hardy-Weinberg equilibrium. Both rs3077 and rs2284553 polymorphisms were not associated with HBV viral load in terms of allelic frequency, genotypic frequency, dominant/recessive gene action. rs9808753 (G allele) was associated with a reduced chance of "undetectable HBV DNA" for patients below the age of 50 years in allelic frequency analysis (odds ratio 0.562; 95% confidence interval, 0.326-0.967; P value = 0.037). IFN-γ receptor-2 gene haplotype block (rs2284553/rs9808753) was not associated with HBV viral activity.
  
  
  CONCLUSIONS
  There was no significant association between HLA-DP polymorphism (rs3077) and IFN-γ receptor-2 gene polymorphism (rs2284553) with viral activity in HBeAg-negative CHB patients. Further studies are required to confirm the association between IFN-γ receptor-2 gene polymorphism (rs9808753) and reduced chance of having "undetectable HBV DNA" in young CHB patients.
authors: Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Hong Kong, China.
authors: Yuk-Fai
authors: YF
authors: Lam
authors: Danny Ka-Ho
authors: DK
authors: Wong
authors: Wai-Kay
authors: WK
authors: Seto
authors: Kelvin Kai-Wang
authors: KK
authors: To
authors: Ivan Fan-Ngai
authors: IF
authors: Hung
authors: James
authors: J
authors: Fung
authors: Ching-Lung
authors: CL
authors: Lai
authors: Man-Fung
authors: MF
authors: Yuen
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D004279:DNA, Viral; D005260:Female; D005787:Gene Frequency; D059867:HLA-DP alpha-Chains / Q000235:genetics*; D006513:Hepatitis B e Antigens; D006515:Hepatitis B virus / Q000235:genetics; D019694:Hepatitis B, Chronic / Q000235:genetics* / Q000821:virology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D017471:Receptors, Interferon / Q000235:genetics*; D015398:Signal Transduction / Q000235:genetics; D019562:Viral Load / Q000235:genetics*; D055815:Young Adult; D000096743:Interferon gamma Receptor
chemical_list: D004279:DNA, Viral; D059867:HLA-DP alpha-Chains; D006513:Hepatitis B e Antigens; D017471:Receptors, Interferon; D000096743:Interferon gamma Receptor; C071172:HLA-DPA1 antigen
keywords: HLA-DP; IFN-γ pathway; chronic hepatitis B