HIV Genetic Diversity: Any Implications for Drug Resistance?

At least nine different genetic HIV–1 subtypes and several circulating recombinant forms exist, which in addition to HIV–1 subgroups and HIV–2 account for the global AIDS pandemic. Even though HIV–1 subtype C and A predominate globally, antiretroviral drugs have been designed based on sequences of clade B reverse transcriptase (RT) and protease enzymes due to the domination of HIV–1 subtype B in highly industrialized countries. Since there is no clarity about possible effects of the genetic diversity of HIV–1 on therapy outcome and drug resistance, multiple studies have been performed with divergent results. Up to now this question remains to be answered.