Analysis of the V3 loop sequences from 10 HIV type 1-infected AIDS patients from Paraguay

HIV-1 consists of eight subtypes, A through H, and group O. The HIV epidemic has only recently come to Paraguay. According to available data from the National AIDS Control Program of Paraguay, there were only 95 individuals known to have had AIDS in the country by the end of 1994. The authors report their findings from the study of HIV-1 from ten people with AIDS living in Asuncion. The subjects were male, with AIDS-related symptoms, and largely contracted HIV through homosexual contact. Some, however, contracted HIV through IV drug use or heterosexually. The nucleic acid sequences obtained from the collected viruses grown in tissue culture have been deposited in GenBank under accession numbers U28949 through U28959. All of the isolated viruses are of subtype B. Virus PY.3616, however, had a V3 loop with the rare motif APGR. The individual from whom this virus was obtained acquired his HIV infection through IV drug use, most probably in Argentina. Two viruses were obtained with V3 loop crown motifs of GPRR and GWRR (PY.12838 and PY.12839), motifs which have not been previously described, but which come close to the V3 loops of HIV-1 isolates found in Brazil with a crown motif GWGR, and also GMGR and GFGR. A motif with an arginine at another position, GRGQ, has been found in HIV-1 subtype H in Cameroon. The different motifs found in the sequences of the Paraguayan patients show greater homogeneity than those of African patients in the Central African Republic and in Paris. The observed diversity reflects the connection of Paraguayans with Brazil and other countries where HIV-1 subtype B prevails. The authors note that their findings are most likely representative of the ongoing, young HIV epidemic in Paraguay.