Molecular Characterization of a Full-Length Genome of a HIV-2 Isolate From India

BACKGROUND: India accounts for 95% of HIV-2 infections in Asia. Molecular epidemiological studies have been performed on HIV-2 partial envelope gene and LTR sequences from isolates in India. Although, a single full-length sequence of an isolate from India is available in the GenBank, a comprehensive molecular analysis of a large number of HIV-2 isolates would be essential for understanding the genomic heterogeneity of HIV-2 isolates prevalent in the country. METHODS: In this study, we determined the complete nucleotide and deduced amino acid sequence of a HIV-2 isolate that was obtained by coculture of infected cells. An extensive full-length genome analysis was performed with sequences available from the GenBank. RESULTS: The isolate belonged to HIV-2 subtype A. Comparison of the genomic sequence with those of the 18 full-length sequences obtained from the GenBank showed the genetic distance ranging from 7.8% with CRIK (subtype A, India) to 30% with EHO (subtype B, Cote d'ivoire). CONCLUSIONS: Phylogenetic analysis indicated that this isolate exhibited close homology with CRIK. Analysis of the gene sequences indicated presence of 2 mutations associated with drug resistance to nucleoside reverse transcriptase inhibitors. Mutations associated with protease inhibitors were not observed in the isolate.