title: [Variants and quasispecies of reverse transcriptase region in polymerase gene of hepatitis B virus during lamivudine treatment].
abstract: OBJECTIVE
  To investigate the variants and quasispecies of reverse transcriptase region in polymerase gene of hepatitis B virus (HBV) during lamivudine treatment and their relationship with genotypes and viral loads.
  
  
  METHODS
  HBV DNA of 117 chronic hepatitis B patients treated with lamivudine were amplified by using PCR. The PCR products including the YMDD motif were sequenced by DNA sequencer, of which, HBV DNA viral loads of 99 patients were determined by real-time PCR and 64 samples were sequenced by Pyrosequencing.
  
  
  RESULTS
  In HBV YMDD variant group and no variant group, the HBV genotypes were 79.6% and 86.7% of type C, 18.5% and 12.7% of type B, 1.9% of A/B recombinant type and 2.6% of type D, respectively. The viral loads (log 10) were 6.5699 and 6.6165, respectively. There was no significant difference in HBV genotypes and viral loads between these two groups. The rtL180M variant was found in association with the rtM204I/V variant, HBV variants and wild-type in YMDD motif all existed together in these two groups.
  
  
  CONCLUSIONS
  HBV variants (quasispecies) in YMDD motif could be quantified by pyrosequencing, which would be a feasible measure during nucleoside or nucleotide analogue therapy against chronic HBV infection.
authors.affiliation: Department of Infectious Diseases, Peking University First Hospital, Beijing 100034, China
authors.forename: Guo-bao
authors.initials: GB
authors.lastname: Tian
authors.forename: Zheng
authors.initials: Z
authors.lastname: Zeng
authors.forename: Zhong-hong
authors.initials: ZH
authors.lastname: Huang
authors.forename: Hai-ying
authors.initials: HY
authors.lastname: Lu
authors.forename: Min
authors.initials: M
authors.lastname: Yu
authors.forename: Wei-bo
authors.initials: WB
authors.lastname: Gong
authors.forename: Dong
authors.initials: D
authors.lastname: Wang
authors.forename: Chong-wen
authors.initials: CW
authors.lastname: Si
mesh_terms: D000998:Antiviral Agents / Q000494:pharmacology*; D005838:Genotype; D006515:Hepatitis B virus / Q000187:drug effects* / Q000235:genetics; D019259:Lamivudine / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D012194:RNA-Directed DNA Polymerase / Q000235:genetics*; D017422:Sequence Analysis, DNA
chemical_list: D000998:Antiviral Agents; D019259:Lamivudine; D012194:RNA-Directed DNA Polymerase