title: Molecular characterization of human immunodeficiency virus (HIV)-1 and -2 in individuals from guinea-bissau with single or dual infections: predominance of a distinct HIV-1 subtype A/G recombinant in West Africa.
abstract: Guinea-Bissau in West Africa has the highest prevalence of human immunodeficiency virus (HIV)-2 infection in the world, but recently the HIV-1 prevalence increased rapidly with the subsequent appearance of HIV-1 and HIV-2 dual infections. Information about the genetic subtypes of HIV in the region is limited. Therefore, we characterized the env V3 region of HIV-1 and HIV-2 variants through direct DNA sequencing of peripheral blood mononuclear cell samples from 18 individuals with HIV-1 only and 9 individuals with dual infection. Phylogenetic analyses of these new sequences and database sequences from other West African countries showed that all HIV-1 and HIV-2 sequences from singly as well as dually infected individuals, except one, clustered among HIV-1 subtype A and HIV-2 subtype A, respectively. Importantly, a majority of the HIV-1 sequences from Guinea-Bissau and neighbouring countries were closely related with the isolates IbNG, DJ263, and DJ264, which share a common subtype A/G recombination pattern. Analysis of pol gene sequences from selected HIV-1 variants showed that "IbNG-like" viruses in Guinea-Bissau are also recombinant, indicating that the HIV-1 epidemic in Guinea-Bissau and neighbouring countries is dominated by an epidemic spread of a distinct subtype A/G recombinant, which is strikingly similar to the epidemic spread of a subtype A/E recombinant in Southeast Asia. Furthermore, the HIV-1 and HIV-2 variants carried by individuals with dual infection were intermixed with variants from singly infected individuals, indicating that variants involved in dual and single infections have common epidemiological histories.
authors.affiliation: Tumor Biology Center, Karolinska Institute, Stockholm, Sweden.
authors.forename: S
authors.initials: S
authors.lastname: Andersson
authors.forename: H
authors.initials: H
authors.lastname: Norrgren
authors.forename: F
authors.initials: F
authors.lastname: Dias
authors.forename: G
authors.initials: G
authors.lastname: Biberfeld
authors.forename: J
authors.initials: J
authors.lastname: Albert
mesh_terms: D000328:Adult; D016208:Databases, Factual; D005260:Female; D005814:Genes, Viral / Q000235:genetics; D015752:Genes, env; D015751:Genes, pol; D014644:Genetic Variation / Q000235:genetics; D006169:Guinea-Bissau / Q000453:epidemiology; D015658:HIV Infections / Q000453:epidemiology / Q000821:virology*; D015497:HIV-1 / Q000145:classification / Q000235:genetics*; D015498:HIV-2 / Q000145:classification / Q000235:genetics*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D011995:Recombination, Genetic; D017422:Sequence Analysis, DNA; D012689:Sequence Homology, Nucleic Acid