title: First WHO International Reference Panel containing hepatitis B virus genotypes A-G for assays of the viral DNA.
abstract: BACKGROUND
  WHO International Standards (IS) are provided for the calibration and validation of diagnostic and screening assays, e.g. for hepatitis B virus (HBV). HBV forms numerous subgenotypes and the current IS for HBV DNA reflects subgenotype A2.
  
  
  OBJECTIVE
  A reference panel with the most prevalent subgenotypes should facilitate evaluation of genotype-specific detection efficiencies.
  
  
  METHODS
  215 HBV positive plasma samples collected worldwide were characterized for HBV markers and sequenced. Fifteen subgenotype A1, A2, B2, B4, C2, D1, D3, E, F2 and G samples were selected for the panel. The lyophilized samples were tested in parallel with the IS in an international collaborative study with 16 laboratories using 13 different nucleic acid amplification techniques (NATs).
  
  
  RESULTS
  Eight of 13 NAT had a HBV DNA detection efficiency which was independent of the genotype and consistent with the IS, while with five assays, certain deviations were noted, particularly with genotype F which was under quantitated or even missed by three assays. The panel was accepted by the WHO as the "1st WHO International Reference Panel for HBV Genotypes for HBV NAT-Based Assays".
  
  
  CONCLUSIONS
  The evaluation of HBV DNA assays should include many different genotypes. The WHO Reference Panel is universally available for manufacturers of HBV DNA assays, diagnostic laboratories and control authorities to facilitate standardized validation of HBV genotype specific detection efficiency of both diagnostic (quantitative and qualitative) and screening NAT assays.
authors.affiliation: Paul-Ehrlich-Institut, Section of Molecular Virology, Langen, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Chudy
authors.forename: K-M
authors.initials: KM
authors.lastname: Hanschmann
authors.forename: J
authors.initials: J
authors.lastname: Kress
authors.forename: S
authors.initials: S
authors.lastname: Nick
authors.forename: R
authors.initials: R
authors.lastname: Campos
authors.forename: U
authors.initials: U
authors.lastname: Wend
authors.forename: W
authors.initials: W
authors.lastname: Gerlich
authors.forename: C M
authors.initials: CM
authors.lastname: Nübling
mesh_terms: D004279:DNA, Viral / Q000235:genetics* / Q000302:isolation & purification; D005838:Genotype; D006509:Hepatitis B / Q000175:diagnosis* / Q000821:virology; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007391:International Cooperation; D025202:Molecular Diagnostic Techniques / Q000379:methods / Q000592:standards*; D012015:Reference Standards; D014773:Virology / Q000379:methods / Q000592:standards*; D014944:World Health Organization
chemical_list: D004279:DNA, Viral