Antiretroviral drug resistance mutations in the reverse transcriptase gene of HIV-1 isolates from Northern Indian patients: a follow-up study.

The viral reverse transcriptase gene was amplified from the plasma of 27 drug-naïve and five drug-experienced HIV patients in Northern India. Follow-up samples of naïve patients after antiretroviral therapy initiation were collected in six patients at 3 months and three patients at 6 months. Phylogenetic analysis revealed two new recombinant forms, CRF_CH and CRF_CK, and an accessory non-nucleoside reverse transcriptase inhibitor mutation E138A, not previously reported from India. The major DRMs found in two 6-month follow-up samples were absent in their baseline blood samples. This is the first follow-up study to determine anti-retroviral drug resistance mutations in Indian HIV patients.