title: Genetic diversity of HCV in Brazil.
abstract: BACKGROUND
  Many studies have documented the molecular epidemiological scenario of HCV within individual Brazilian states, but we still have an incomplete understanding of the dispersion dynamics of the virus in different regions throughout the country.
  
  
  METHODS
  A total of 676 HCV NS5B gene sequences of subtypes 1a (n=321), 1b (n=170) and 3a (n=185), isolated from seven different Brazilian states covering four out of five regions were analysed in the present study. We also analysed 22 HCV NS5B gene sequences of minor genetic variants including genotype 2 (n=13), genotype 4 (n=6) and subtype 5a (n=3). Brazilian HCV sequences were aligned with sequences of non-Brazilian origin and subjected to maximum likelihood phylogenetic analyses.
  
  
  RESULTS
  These analyses revealed that the Brazilian HCV epidemic resulted from multiple introductions and autochthonous transmission of subtypes 1a, 1b, 3a and genotypes 2, 4 and 5. Brazilian HCV subtype 1a epidemic is dominated by the dissemination of one major clade; while Brazilian HCV subtypes 1b and 3a epidemics are characterized by concurrent dissemination of several independent HCV lineages. Some HCV Brazilian lineages of subtypes 1a, 1b, 2b and 3a were successful in becoming established and disseminated through several regions in the country. Despite significant phylogenetic intermixing of Brazilian sequences, the distribution of HCV strains from different states across lineages was not completely homogeneous.
  
  
  CONCLUSIONS
  These results demonstrate the existence of multiple introductions and local propagation of both prevalent and uncommon HCV genetic variants in Brazil and identify some major Brazilian HCV clades with nationwide dissemination. This study also suggests that the observed HCV diversity in Brazil has been shaped by both frequent viral migration among regions and in situ viral dissemination.
authors.affiliation: Laboratório de Hepatites Virais, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil. elampe@ioc.fiocruz.br
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Lampe
authors.forename: Lia
authors.initials: L
authors.lastname: Lewis-Ximenez
authors.forename: Marcia P
authors.initials: MP
authors.lastname: Espírito-Santo
authors.forename: Nathália M
authors.initials: NM
authors.lastname: Delvaux
authors.forename: Sergio A
authors.initials: SA
authors.lastname: Pereira
authors.forename: Allan
authors.initials: A
authors.lastname: Peres-da-Silva
authors.forename: Regina M B
authors.initials: RM
authors.lastname: Martins
authors.forename: Marcelo A
authors.initials: MA
authors.lastname: Soares
authors.forename: André F
authors.initials: AF
authors.lastname: Santos
authors.forename: Luãnna L
authors.initials: LL
authors.lastname: Vidal
authors.forename: Fabiana N
authors.initials: FN
authors.lastname: Germano
authors.forename: Ana Maria B
authors.initials: AM
authors.lastname: de Martinez
authors.forename: Rossana
authors.initials: R
authors.lastname: Basso
authors.forename: João R Rebello
authors.initials: JR
authors.lastname: Pinho
authors.forename: Fernanda M
authors.initials: FM
authors.lastname: Malta
authors.forename: Michele
authors.initials: M
authors.lastname: Gomes-Gouvêa
authors.forename: Ricardo A
authors.initials: RA
authors.lastname: Moliterno
authors.forename: Dennis A
authors.initials: DA
authors.lastname: Bertolini
authors.forename: Mayara A T
authors.initials: MA
authors.lastname: Fujishima
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Bello
mesh_terms: D001483:Base Sequence; D001938:Brazil / Q000453:epidemiology; D058872:Epidemics; D014644:Genetic Variation; D005838:Genotype; D016174:Hepacivirus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D006526:Hepatitis C / Q000453:epidemiology* / Q000635:transmission; D006801:Humans; D017720:Molecular Epidemiology; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D017423:Sequence Analysis, RNA; D017361:Viral Nonstructural Proteins / Q000235:genetics*; D012324:RNA-Dependent RNA Polymerase
chemical_list: D012367:RNA, Viral; D017361:Viral Nonstructural Proteins; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase