First Report of Human Immunodeficiency Virus Type 1 Circulating Recombinant Form 02_AG Recombinant Strain of African Origin from North India

Problem statement: Human Immunodeficiency Virus Type-1 (HIV-1) displays extensive genetic diversity globally which poses a serious challenge in making efficacious vaccine and developing effective therapeutic interventions. HIV-1 epidemic in India is largely driven by genetic subtype C but lately a number of reports suggest the presence of circulating recombinant forms and unique recombinant forms from different states of India. Approach: We analyzed 13 envelope sequences spanning the region from V1-V5 from three regions of North India and subjected to extensive genetic analysis. Results: We identified equal numbers (n = 6) of subtype C and CRF02_AG recombinant strain and a single subtype B-specific envelope. The extensive phylogenetic analysis of our CRF02_AG strains indicate that they are closely related to Central and Central-West African strains. The analysis of intra-subtype nucleotide distance revealed that the subtype C sequences are significantly more divergent and diverse than CRF02_AG strains (p<0.004). Conclusion: Appearance of CRF02_AG strain of African origin among commercial sex workers from Delhi and Punjab region of India is reported for the first time which needs to be monitored for its pathogenesis and its ability to recombine with the circulating strains.