Author:
D’arc Mirela,Ayouba Ahidjo,Esteban Amandine,Learn Gerald H.,Boué Vanina,Liegeois Florian,Etienne Lucie,Tagg Nikki,Leendertz Fabian H.,Boesch Christophe,Madinda Nadège F.,Robbins Martha M.,Gray Maryke,Cournil Amandine,Ooms Marcel,Letko Michael,Simon Viviana A.,Sharp Paul M.,Hahn Beatrice H.,Delaporte Eric,Mpoudi Ngole Eitel,Peeters Martine
Abstract
HIV-1, the cause of AIDS, is composed of four phylogenetic lineages, groups M, N, O, and P, each of which resulted from an independent cross-species transmission event of simian immunodeficiency viruses (SIVs) infecting African apes. Although groups M and N have been traced to geographically distinct chimpanzee communities in southern Cameroon, the reservoirs of groups O and P remain unknown. Here, we screened fecal samples from western lowland (n= 2,611), eastern lowland (n= 103), and mountain (n= 218) gorillas for gorilla SIV (SIVgor) antibodies and nucleic acids. Despite testing wild troops throughout southern Cameroon (n= 14), northern Gabon (n= 16), the Democratic Republic of Congo (n= 2), and Uganda (n= 1), SIVgor was identified at only four sites in southern Cameroon, with prevalences ranging from 0.8–22%. Amplification of partial and full-length SIVgor sequences revealed extensive genetic diversity, but all SIVgor strains were derived from a single lineage within the chimpanzee SIV (SIVcpz) radiation. Two fully sequenced gorilla viruses from southwestern Cameroon were very closely related to, and likely represent the source population of, HIV-1 group P. Most of the genome of a third SIVgor strain, from central Cameroon, was very closely related to HIV-1 group O, again pointing to gorillas as the immediate source. Functional analyses identified the cytidine deaminase APOBEC3G as a barrier for chimpanzee-to-gorilla, but not gorilla-to-human, virus transmission. These data indicate that HIV-1 group O, which spreads epidemically in west central Africa and is estimated to have infected around 100,000 people, originated by cross-species transmission from western lowland gorillas.
Funder
National Institutes of Health
Agence Nationale de Recherches sur le Sida et les Hepatites Virales
Publisher
Proceedings of the National Academy of Sciences