Evolution of HIV-1 in India.

Nearly 25 years after the discovery of the human immunodeficiency virus type 1 (HIV-1) effective control of the AIDS pandemic remains elusive. At the root of this challenge is the evolution of this virus to elude immune control. Error-prone nature of replication and retro-transcription is the hallmark of this virus. This fidelity of replication in HIV-1 is due to the absence of proof-reading/repair and post-replicative error correction mechanisms that normally operate during replication of DNA viruses. Advances in sequencing technology and expanded disease surveillance have allowed researchers to characterize the variation in HIV-1 around the world and within individual patient overtime. Although HIV-1 has been classified into distinct subtypes, the classification does not reflect dynamic genetic evolution of HIV-1 through which new strains are constantly emerging. The resultant viral diversity has implications for differential rates of disease progression in different geographical areas, differential responses to antiretroviral therapy (including the development of resistance), and vaccine development. In this review evolution of HIV-1 in India is discussed.