title: Test of IL28B polymorphisms in chronic hepatitis C patients treated with PegIFN and ribavirin depends on HCV genotypes: results from a meta-analysis.
abstract: BACKGROUND
  Many studies have been published on the association between single nucleotide polymorphisms (SNP) near the IL28B gene and response to the combined treatments of pegylated-interferon (PegIFN) and ribavirin (RBV) in chronic HCV-infected patients, but without identical conclusions. The aim of this study was to assess impact of the IL28B polymorphisms on the effect of HCV standard treatment using meta-analysis based method.
  
  
  METHODS
  Association studies between polymorphisms of rs12979860 or rs8099917 and response to PegIFN/RBV treatment in chronic HCV patients were retrieved from PubMed. Data of qualified studies on sustained virological response (SVR) in different genotypes were extracted and analyzed using meta-analysis method in Stata 10 software.
  
  
  RESULTS
  Thirty-four papers, containing 46 independent studies, were included in the analysis. In the HCV G1/4 patients without treatment history, individuals carrying rs12979860 CC genotype were more likely to achieve SVR (OR 3.97, 95%CI 3.29-4.80) compared to those carrying CT/TT genotypes. Similar results were observed in the HCV G1/4 patients with unsuccessful or unknown treatment history (OR 3.76, 95%CI 2.67-5.28) or in the patients co-infected with human immunodeficiency virus (OR 5.20, 95%CI 3.04-8.90). However, associations could not be observed in HCV G2/3 patients. For rs8099917, similar results were obtained for genotype TT compared to genotypes TG/GG, indicating that TT genotype was significantly associated with better treatment response in patients infected with genotype 1 or 4 HCV, but not genotype 2 or 3 HCV.
  
  
  CONCLUSIONS
  Polymorphisms of rs12979860 and rs8099917 near IL28B only associate with the treatment response to PegIFN/RBV in patients infected with HCV genotype 1 or 4 but not with genotype 2 or 3, irrespective of the previous treatment history or HIV co-infected status. Therefore, identification of IL28B genotypes is necessary only in patients infected with relatively difficult-to-treat genotype 1 or 4 HCV.
authors.affiliation: Division of Clinical Epidemiology, First Hospital of Jilin University, Changchun, China.
authors.forename: Zhifang
authors.initials: Z
authors.lastname: Jia
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Ding
authors.forename: Suyan
authors.initials: S
authors.lastname: Tian
authors.forename: Junqi
authors.initials: J
authors.lastname: Niu
authors.forename: Jing
authors.initials: J
authors.lastname: Jiang
mesh_terms: D000998:Antiviral Agents / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics / Q000302:isolation & purification*; D019698:Hepatitis C, Chronic / Q000188:drug therapy / Q000235:genetics*; D006801:Humans; D016898:Interferon-alpha / Q000008:administration & dosage / Q000627:therapeutic use*; D007372:Interferons; D007378:Interleukins / Q000235:genetics*; D011092:Polyethylene Glycols / Q000008:administration & dosage / Q000627:therapeutic use*; D011110:Polymorphism, Genetic; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000627:therapeutic use; D012254:Ribavirin / Q000008:administration & dosage / Q000627:therapeutic use*; D000095022:Interferon Lambda
chemical_list: D000998:Antiviral Agents; D016898:Interferon-alpha; D007372:Interferons; D007378:Interleukins; D011092:Polyethylene Glycols; D011994:Recombinant Proteins; D012254:Ribavirin; C000624353:interferon-lambda, human; D000095022:Interferon Lambda; C100416:peginterferon alfa-2a