title: Phylogeny and molecular genetic parameters of different stages of hepatitis B virus infection in patients from the Brazilian Amazon.
abstract: A fragment of 600 bp of the gene which codes for the surface antigen of hepatitis B virus (HBV) was amplified and sequenced from patients who were born in five states of the Brazilian Amazon (Amazonas, Pará, Acre, Rondônia and Tocantins). A total of 44 sequences were used for the estimation of molecular genetic parameters and phylogenetic analyses. Compared with patients who were asymptomatic, those who had acute hepatitis and chronic liver disease had higher levels of genetic variability and higher rates of nucleotide substitutions. The analysis of transition and transversion substitutions showed that transition-type substitutions predominated. In chronic liver disease carriers, transversion-type substitutions showed phylogenetic saturation. In general, all of the analyses carried out in this study showed an association between patterns of changes in molecular genetic parameters and the stage of disease progression. Phylogenetic analysis using the HKY85 model of evolution identified 41 individuals as genotype A, suggesting its predominance in the Amazon region, one individual as genotype C, and one individual closely related to genotypes E and F.
authors.affiliation: Centro de Apoio Multidisciplinar, Instituto de Ciências Biológicas, Universidade Federal do Amazonas, Manaus, AM, Brazil.
authors.forename: Cíntia Mara
authors.initials: CM
authors.lastname: de Oliveira
authors.forename: Izeni Pires
authors.initials: IP
authors.lastname: Farias
authors.forename: José Carlos
authors.initials: JC
authors.lastname: Ferraz da Fonseca
authors.forename: Leila Melo
authors.initials: LM
authors.lastname: Brasil
authors.forename: Rita
authors.initials: R
authors.lastname: de Souza
authors.forename: Spartaco
authors.initials: S
authors.lastname: Astolfi-Filho
mesh_terms: D000208:Acute Disease; D001483:Base Sequence; D001938:Brazil / Q000453:epidemiology; D017931:DNA Primers / Q000235:genetics; D004279:DNA, Viral / Q000235:genetics; D019143:Evolution, Molecular; D005814:Genes, Viral; D014644:Genetic Variation; D005838:Genotype; D006509:Hepatitis B / Q000453:epidemiology / Q000821:virology*; D006514:Hepatitis B Surface Antigens / Q000235:genetics; D006515:Hepatitis B virus / Q000145:classification / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification*; D019694:Hepatitis B, Chronic / Q000453:epidemiology / Q000821:virology; D006801:Humans; D008957:Models, Genetic; D008967:Molecular Biology; D010802:Phylogeny
chemical_list: D017931:DNA Primers; D004279:DNA, Viral; D006514:Hepatitis B Surface Antigens