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.