Frequency of drug-resistant variants of HIV-1 coexistent with wild-type in treatment-naive patients of India.

CONTEXT: Over the past few years, reports of emergence and transmission of drug-resistant strains of HIV have increased, especially in western countries. In the context of increased widespread use of zidovudine- and lamivudine-based combinations in India, coupled with the genetic diversity of HIV, it is essential to generate preliminary data on the frequency of zidovudine- and lamivudine-resistant variants of HIV-1 in North India.
OBJECTIVES: In the present study, the authors screened for mutations in the pol gene of HIV-1 associated with resistance to zidovudine and lamivudine in HIV-infected treatment-naive patients from North India. DESIGN AND PATIENTS: The mutations were screened at codons 70 and 215 (conferring resistance to zidovudine) and at codon 184 (conferring resistance to lamivudine) by using a nested amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) approach from the proviral DNA of 60 patients.
RESULTS: Most of the patients showed a mixture of both wild-type and mutant virus. In all but 1 patient, wild-type virus was observed with respect to each codon. Mutant variants were also observed in many patients, especially at codon 70 (48 patients [80%]) and codon 184 (19 patients [31.67%]). In contrast, the frequency of mutation at codon 215 was found to be very low (1 patient [1.67%]).
CONCLUSIONS: In this sample of treatment-naive HIV-1-infected patients in North India, a high proportion of mutant variants harbored mutations in the pol gene at codons- 70 and 184 coexisting with wild-type HIV-1.