title: [Development and validation of a specific method for relative HBV-genotype G (G-HBV) quantification in the context of co-infection with other genotypes].
abstract: OBJECTIVE
  A detection and quantification method specific of genotype G hepatitis B virus (G-HBV) was developed and used to study the epidemiology and evolution of G-HBV co-infection during antiviral therapy.
  
  
  METHODS
  A multiplex real time PCR was developed and validated on A-HBV and G-HBV plasmid mixes. G-HBV infection was sought for on chronic hepatitis B carriers followed in our institution.
  
  
  RESULTS
  Two primers, flanking the specific G-HBV 36 nucleotide insertion and two probes, including one specific for the insertion, were validated for a multiplex real time PCR. This new tool was well correlated to commercially available quantification systems within a 2 to 7 log(10) IU/mL range. On A- and G-HBV clonal mixes, G-HBV was quantified with a precision between 5 to 10%. On HBV-HIV infected patients, a 25% G-HBV prevalence was found, while it was below 1% in HBV mono-infected patients. Longitudinal G-HBV quantifications on five treated patients indicate that G-HBV is not selected by antiviral treatment.
  
  
  CONCLUSIONS
  A specific method for G-HBV quantification within multi-genotype mixes was set up. The important G-HBV prevalence in HIV patients was unexpected. Our data are not in favour of an intrinsic resistance of G-HBV to current antivirals.
authors.affiliation: ER 1, université Pierre-et-Marie-Curie, 105, boulevard de l'Hôpital, 75013 Paris, France.
authors.forename: N
authors.initials: N
authors.lastname: Désiré
authors.forename: T
authors.initials: T
authors.lastname: Sanchis
authors.forename: F
authors.initials: F
authors.lastname: Ben Moussa
authors.forename: H
authors.initials: H
authors.lastname: Stitou
authors.forename: C
authors.initials: C
authors.lastname: Katlama
authors.forename: V
authors.initials: V
authors.lastname: Thibault
mesh_terms: D000998:Antiviral Agents / Q000627:therapeutic use; D001483:Base Sequence; D015897:Comorbidity; D003199:Computer Systems; D017124:Conserved Sequence; D004279:DNA, Viral / Q000235:genetics; D024882:Drug Resistance, Viral; D005500:Follow-Up Studies; D005838:Genotype; D015658:HIV Infections / Q000453:epidemiology; D006509:Hepatitis B / Q000188:drug therapy / Q000453:epidemiology / Q000821:virology*; D006515:Hepatitis B virus / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D008969:Molecular Sequence Data; D016254:Mutagenesis, Insertional; D015345:Oligonucleotide Probes; D016133:Polymerase Chain Reaction / Q000379:methods*; D015995:Prevalence; D011933:Reagent Kits, Diagnostic; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D019562:Viral Load
chemical_list: D000998:Antiviral Agents; D004279:DNA, Viral; D015345:Oligonucleotide Probes; D011933:Reagent Kits, Diagnostic