title: [Hepatitis B virus genotypes and the heterogeneity of its polymerase gene].
abstract: OBJECTIVE
  To study the heterogeneity of polymerase gene (P gene) within hepatitis B virus (HBV) genotypes based on a systematic analysis of 202 HBV P genes, providing some useful references for further studies on the relationship among HBV genotypes, P gene mutations, replication and nucleoside analogues drug-resistance.
  
  
  METHODS
  202 HBV complete sequences containing P genes were obtained from GenBank and were analysed using computer softwares.
  
  
  RESULTS
  There were some genotype-related characteristics of HBV P genes. As reverse transcriptase domain was concerned, there were more amino acid divergences in genotype C and D compared with these in genotype A. There were also amino acid substitutions in the A-F conserved regions of the reverse transcriptase domain within and between HBV genotypes.
  
  
  CONCLUSIONS
  There are divergences of P genes and amino acids within and between HBV genotypes, which should be considered when amino acid changes are analyzed whether they are proposed to be drug-resistance mutations or the results from quasispecies-selected. Moreover, these divergences may affect the antiviral effect of nucleoside analogues on HBV with different genotypes.
authors.affiliation: Department of Infectious Diseases, Nafang Hospital, First Military Medical University, Guangzhou 510515, China.
authors.forename: Guo-bing
authors.initials: GB
authors.lastname: Zeng
authors.forename: Shu-juan
authors.initials: SJ
authors.lastname: Wen
authors.forename: Jian
authors.initials: J
authors.lastname: Sun
authors.forename: Ze-yan
authors.initials: ZY
authors.lastname: Guo
authors.forename: Zhan-hui
authors.initials: ZH
authors.lastname: Wang
authors.forename: Kang-xian
authors.initials: KX
authors.lastname: Luo
authors.forename: Li
authors.initials: L
authors.lastname: Yan
authors.forename: Jin-lin
authors.initials: JL
authors.lastname: Hou
mesh_terms: D000595:Amino Acid Sequence; D004279:DNA, Viral / Q000235:genetics; D004259:DNA-Directed DNA Polymerase / Q000235:genetics*; D015684:Gene Products, pol / Q000235:genetics; D018740:Genetic Heterogeneity; D005838:Genotype; D006515:Hepatitis B virus / Q000235:genetics* / Q000502:physiology; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny
chemical_list: D004279:DNA, Viral; D015684:Gene Products, pol; C066027:P protein, Hepatitis B virus; D004259:DNA-Directed DNA Polymerase