title: Tax gene characterization of human T-lymphotropic virus type 1 strains from Brazilian HIV-coinfected patients.
abstract: The tax gene of human T-lymphotropic virus type 1 (HTLV-1) diverges among isolates according to geographic regions and has been classified into two genotypes: taxA and taxB. In Brazil, taxA is the most prevalent genotype in symptomatic and asymptomatic carriers. Few studies have been conducted in HIV-infected patients. The present study characterized the tax gene (1059 bp) in 13 Brazilian HIV-1/HTLV-1-coinfected patients from the south and southeast regions. The results confirmed the transcontinental HTLV-1 subgroup A of the Cosmopolitan subtype and showed high nucleotide similarity both among Brazilian sequences and in relation to the ATK prototype (99.5% and 99.2%, respectively). Six nucleotide substitutions were highly conserved among isolates, ranging from 76.9% to 100%: C7401T, T7914C, C7920T, C7982T, G8231A, and A8367C. The presence of the Brazilian molecular signature of genotype taxA was confirmed in all of the isolates, and they clustered into two Latin American clusters, which confirms the double introduction of HTLV-1 in Brazil.
authors.affiliation: Laboratório de Retrovirus, Centro de Virologia, Instituto Adolfo Lutz, Secretaria de Estado da Saúde de São Paulo, São Paulo, S.P., Brazil.
authors.forename: Mariana Cavalheiro
authors.initials: MC
authors.lastname: Magri
authors.forename: Luis Fernando de Macedo
authors.initials: LF
authors.lastname: Brigido
authors.forename: Rosangela
authors.initials: R
authors.lastname: Rodrigues
authors.forename: Helena Kaminami
authors.initials: HK
authors.lastname: Morimoto
authors.forename: Adele
authors.initials: A
authors.lastname: Caterino-de-Araujo
mesh_terms: D001938:Brazil; D017124:Conserved Sequence; D016355:Genes, pX; D005838:Genotype; D015658:HIV Infections / Q000150:complications*; D015497:HIV-1 / Q000302:isolation & purification; D015490:HTLV-I Infections / Q000150:complications* / Q000821:virology*; D015368:Human T-lymphotropic virus 1 / Q000235:genetics* / Q000302:isolation & purification; D006801:Humans; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D017354:Point Mutation; D017422:Sequence Analysis, DNA