title: Origin of HIV-1 in the chimpanzee Pan troglodytes troglodytes.
abstract: The human AIDS viruses human immunodeficiency virus type 1 (HIV-1) and type 2 (HIV-2) represent cross-species (zoonotic) infections. Although the primate reservoir of HIV-2 has been clearly identified as the sooty mangabey (Cercocebus atys), the origin of HIV-1 remains uncertain. Viruses related to HIV-1 have been isolated from the common chimpanzee (Pan troglodytes), but only three such SIVcpz infections have been documented, one of which involved a virus so divergent that it might represent a different primate lentiviral lineage. In a search for the HIV-1 reservoir, we have now sequenced the genome of a new SIVcpzstrain (SIVcpzUS) and have determined, by mitochondrial DNA analysis, the subspecies identity of all known SIVcpz-infected chimpanzees. We find that two chimpanzee subspecies in Africa, the central P. t. troglodytes and the eastern P. t. schweinfurthii, harbour SIVcpz and that their respective viruses form two highly divergent (but subspecies-specific) phylogenetic lineages. All HIV-1 strains known to infect man, including HIV-1 groups M, N and O, are closely related to just one of these SIVcpz lineages, that found in P. t. troglodytes. Moreover, we find that HIV-1 group N is a mosaic of SIVcpzUS- and HIV-1-related sequences, indicating an ancestral recombination event in a chimpanzee host. These results, together with the observation that the natural range of P. t. troglodytes coincides uniquely with areas of HIV-1 group M, N and O endemicity, indicate that P. t. troglodytes is the primary reservoir for HIV-1 and has been the source of at least three independent introductions of SIVcpz into the human population.
authors.affiliation: Department of Medicine, University of Alabama at Birmingham, 35294, USA.
authors.forename: F
authors.initials: F
authors.lastname: Gao
authors.forename: E
authors.initials: E
authors.lastname: Bailes
authors.forename: D L
authors.initials: DL
authors.lastname: Robertson
authors.forename: Y
authors.initials: Y
authors.lastname: Chen
authors.forename: C M
authors.initials: CM
authors.lastname: Rodenburg
authors.forename: S F
authors.initials: SF
authors.lastname: Michael
authors.forename: L B
authors.initials: LB
authors.lastname: Cummins
authors.forename: L O
authors.initials: LO
authors.lastname: Arthur
authors.forename: M
authors.initials: M
authors.lastname: Peeters
authors.forename: G M
authors.initials: GM
authors.lastname: Shaw
authors.forename: P M
authors.initials: PM
authors.lastname: Sharp
authors.forename: B H
authors.initials: BH
authors.lastname: Hahn
mesh_terms: D000163:Acquired Immunodeficiency Syndrome / Q000453:epidemiology / Q000635:transmission* / Q000821:virology; D000350:Africa, Central / Q000453:epidemiology; D000351:Africa, Eastern / Q000453:epidemiology; D000818:Animals; D018420:Ape Diseases / Q000821:virology*; D002522:Chlorocebus aethiops; D004272:DNA, Mitochondrial / Q000235:genetics; D004279:DNA, Viral; D004196:Disease Outbreaks; D004197:Disease Reservoirs; D019143:Evolution, Molecular; D005260:Female; D016679:Genome, Viral; D015497:HIV-1 / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D006801:Humans; D008460:Meat / Q000821:virology; D008969:Molecular Sequence Data; D002679:Pan troglodytes / Q000145:classification / Q000821:virology*; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011995:Recombination, Genetic; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D016097:Simian Acquired Immunodeficiency Syndrome / Q000821:virology*; D015302:Simian Immunodeficiency Virus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D015047:Zoonoses / Q000635:transmission / Q000821:virology