Antiretroviral-Drug Resistant Mutations and Genetic Diversity in HIV-1 Infected Individuals in Nigeria

Introduction: Despite the success derived from antiretroviral therapy, drug resistance (DR) mutations are known to develop and are major impediments to treatment of HIV patients. Therefore, periodic assessment of HIVDR is needed to ensure continuous HAART efficacy. This study assessed the magnitude of drug resistance as well as HIV genetic variability in drug-naive and treated patients in Nigeria. Methodology: Genotypic analysis was performed by sequencing plasma specimens from 40 individuals in a cross sectional study involving 202 HIV infected patients from all the six geopolitical zones of Nigeria. Sequences were analyzed for presence of HIVDR mutation using the algorithm in Stanford HIVDR database and confirmed by IAS-USA 2009 mutation list. Phylogenetic and recombination analyses were done using PAUP V4.0 and REGA V2.0 respectively. Results: Major DR mutations were detected in the reverse transcriptase (RT) gene of 5 (33%) drug experienced and 2 (8%) na?ve patients. Most common mutations were M184V and K103N with no protease (PR) mutations detected. Thymidine analogue mutations (TAMs) and a complex multi resistance mutation Q151M were detected in 3 samples. Polymorphic substitutions were observed in both PR and RT gene. Phylogenetic analysis revealed Group M isolates of G (20), J (1), circulating recombinant forms: CRF02_AG (14), CRF-18-cpx (1), CRF06_cpx (3) and a unique AD recombinant (1). Conclusion: Our findings corroborate previous studies on circulating DR viruses in Nigeria while genetic diversity is on the increase. In view of ART scale-up, monitoring the resistance pattern and genetic diversity will aid in appropriate prevention strategies.