title: Description of the first full-length HIV type 1 subtype F1 strain in Argentina: implications for the origin and dispersion of this subtype in South America.
abstract: HIV-1 subtype F1 in South America is mainly found as part of diverse BF1 recombinant forms and only five full-length "pure" F1 strains from Brazil were characterized to date. In the present study we describe the first near full-length sequence of a nonrecombinant F1 HIV-1 strain from Argentina, and explore the epidemiological history of this subtype in South America. Three separate phylogenetic analyses were carried out: with all available F1 full-length sequences, with concatenated F1 sequences contained in F1 and BF1 strains, and with partial F1 env sequences derived from worldwide strains. All analyses were consistent in showing a local origin of the newly reported Argentine subtype F1 strain, and a common ancestry of the South American subtype F1 sequences, present either in pure or recombinant genomes. By coalescent analysis, the onset date of the HIV-1 subtype F1 epidemic in South America was estimated to be around the late 1970s. The results indicate for the first time that nonrecombinant F1 HIV-1 strains are present in Argentina, and suggest that the subtype F1 epidemic in South America was initiated by the introduction of a very small group of genetically related viruses during late 1970s.
authors.affiliation: Laboratorio de Biología Celular y Retrovirus-CONICET, Hospital de Pediatría "J. P. Garrahan," Buenos Aires, Argentina. paulicino@garrahan.gov.ar
authors.forename: Paula C
authors.initials: PC
authors.lastname: Aulicino
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Bello
authors.forename: Carlos
authors.initials: C
authors.lastname: Rocco
authors.forename: Héctor
authors.initials: H
authors.lastname: Romero
authors.forename: Andrea
authors.initials: A
authors.lastname: Mangano
authors.forename: Mariza G
authors.initials: MG
authors.lastname: Morgado
authors.forename: Luisa
authors.initials: L
authors.lastname: Sen
mesh_terms: D001118:Argentina; D001483:Base Sequence; D016679:Genome, Viral; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D007223:Infant; D008969:Molecular Sequence Data; D010802:Phylogeny; D011995:Recombination, Genetic; D016415:Sequence Alignment; D013020:South America