Human infection by genetically diverse SIVSM-related HIV-2 in West Africa

• Published in: Nature (London) Vol. 358; no. 6386; pp. 495 - 499
• Main Authors: FENG GAO, LING YUE, WHITE, A. T, PAPPAS, P. G, BARCHUE, J, HANSON, A. P, GREENE, B. M, SHARP, P. M, SHAW, G. M, HAHN, B. H
• Format: Journal Article
• Language: English
• Published: London Nature Publishing 06-08-1992; Nature Publishing Group
• Subjects: Acquired immune deficiency syndrome; Adult; AIDS; AIDS/HIV; Amino Acid Sequence; Base Sequence; Biological and medical sciences; Farmworkers; Genes, env; Genes, pol; Genetic Variation; Genotypes; HIV Infections - microbiology; HIV Long Terminal Repeat; HIV-2 - genetics; Humans; Immunodeficiencies; Immunodeficiencies. Immunoglobulinopathies; Immunopathology; Liberia; Male; Medical research; Medical sciences; Middle Aged; Molecular Sequence Data; Phylogeny; Simian Immunodeficiency Virus - genetics; Urban populations; Viruses; Liberia; Africa; Human; Immunopathology; Genetic variability; Nucleotide sequence; Retroviridae; AIDS; Hemopathy; Phylogeny; HIV-2 virus; Infection; Virus; Molecular evolution; Viral disease; Lentivirinae; Human immunodeficiency virus; Mutation; Clinical isolate
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/358495a0

Our understanding of the biology and origins of human immunodeficiency virus type 2 (HIV-2) derives from studies of cultured isolates from urban populations experiencing epidemic infection and disease. To test the hypothesis that such isolates might represent only a subset of a larger, genetically more diverse group of viruses, we used nested polymerase chain reactions to characterize HIV-2 sequences in uncultured mononuclear blood cells of two healthy Liberian agricultural workers, from whom virus isolation was repeatedly unsuccessful, and from a culture-positive symptomatic urban dweller. Analysis of pol, env and long terminal repeat regions revealed the presence of three highly divergent HIV-2 strains, one of which (from one of the healthy subjects) was significantly more closely related to simian immunodeficiency viruses infecting sooty mangabeys and rhesus macaques (SIVSM/SIVMAC) than to any virus of human derivation. This subject also harboured multiply defective viral genotypes that resulted from hypermutation of G to A bases. Our results indicate that HIV-2, SIVSM and SIVMAC comprise a single, highly diverse group of lentiviruses which cannot be separated into distinct phylogenetic lineages according to species of origin.