HIV Intersubtype Recombination: Discordance and Harmony of In Vitro Experiments and Observations from Sequence Analysis of Circulating Recombinants

Recombination has been identified to influencethe rate and paths of evolution in many species.Retroviral recombination was initially identified inavian tumor viruses (Vogt P, Virology 1971;46:947-52),while the impact of recombination on the evolutionof HIV-1 has been documented recently, showingthat at least 20% of the circulating strains areintersubtype recombinants (Peeters M, Aids 2000;14:S129-40). Homologous recombination in HIV-1can be differentiated at three levels: between strainsof the same subtype (intrasubtype), different subtypes(intersubtype) and between strains of differentgroups (intergroup).