title: Characterization of hepatitis B virus (HBV) genotypes in patients from Rondônia, Brazil.
abstract: BACKGROUND
  Hepatitis B virus (HBV) can be classified into nine genotypes (A-I) defined by sequence divergence of more than 8% based on the complete genome. This study aims to identify the genotypic distribution of HBV in 40 HBsAg-positive patients from Rondônia, Brazil. A fragment of 1306 bp partially comprising surface and polymerase overlapping genes was amplified by PCR. Amplified DNA was purified and sequenced. Amplified DNA was purified and sequenced on an ABI PRISM® 377 Automatic Sequencer (Applied Biosystems, Foster City, CA, USA). The obtained sequences were aligned with reference sequences obtained from the GenBank using Clustal X software and then edited with Se-Al software. Phylogenetic analyses were conducted by the Markov Chain Monte Carlo (MCMC) approach using BEAST v.1.5.3.
  
  
  RESULTS
  The subgenotypes distribution was A1 (37.1%), D3 (22.8%), F2a (20.0%), D4 (17.1%) and D2 (2.8%).
  
  
  CONCLUSIONS
  These results for the first HBV genotypic characterization in Rondônia state are consistent with other studies in Brazil, showing the presence of several HBV genotypes that reflects the mixed origin of the population, involving descendants from Native Americans, Europeans, and Africans.
authors.affiliation: Research Center for Tropical Medicine--CEPEM/Tropical Pathology Research Institute-IPEPATRO. Porto Velho, RO, Brazil.
authors.forename: Alcione O
authors.initials: AO
authors.lastname: Santos
authors.forename: Mónica V
authors.initials: MV
authors.lastname: Alvarado-Mora
authors.forename: Lívia
authors.initials: L
authors.lastname: Botelho
authors.forename: Deusilene S
authors.initials: DS
authors.lastname: Vieira
authors.forename: João R Rebello
authors.initials: JR
authors.lastname: Pinho
authors.forename: Flair J
authors.initials: FJ
authors.lastname: Carrilho
authors.forename: Eduardo R
authors.initials: ER
authors.lastname: Honda
authors.forename: Juan M
authors.initials: JM
authors.lastname: Salcedo
mesh_terms: D000293:Adolescent; D000328:Adult; D001938:Brazil; D016000:Cluster Analysis; D005260:Female; D005838:Genotype; D006509:Hepatitis B / Q000821:virology*; D006515:Hepatitis B virus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D014764:Viral Proteins / Q000235:genetics; D055815:Young Adult
chemical_list: D014764:Viral Proteins