Identification of an env G subtype and heterogeneity of HIV-1 strains in the Russian Federation and Belarus

Objective
To identify HIV-1 envelope sequence subtypes in infected individuals from the Russian Federation and Belarus.

Patients
A cohort of children infected after exposure to non-sterile needles during the 1988–1989 HIV-1 epidemic in southern Russia (n = 20) and HIV-1-seropositive individuals from Russia (n = 1) and Belarus (n = 7) infected via sexual transmission.

Methods
DNA samples derived from peripheral blood mononuclear cells were analysed for their HIV-1 genotypes by the heteroduplex mobility assay (HMA). The 1.3 kilobase-pair env gene fragments encoding a portion of gp120 were amplified by nested polymerase chain reaction, cloned and sequenced. The env sequences derived from these patients were aligned and phylogenetic neighbour-joining and maximum parsimony-derived trees generated.

Results
The env sequences derived from eight individuals infected in Russia and Belarus belong to subtype A (one), B (four), C (two), and D (one). Sequences derived from children, infected during parenteral manipulations in southern Russia, and one mother were closely related, but highly divergent, as a group, from all prototypic strains (genetic divergence, 17.2–22.9%). However, they clustered together with env sequences of the V1525 and LBV21–7 isolates from Gabon, recently described to be members of a new HIV-1 env subtype G.

Conclusion
Extensive heterogeneity of HIV-1 subtypes was evident in the Russian Federation and Belarus. Our data also support the existence of an HIV-1 env genetic subtype G, and such isolates are now apparently present on both the African and European continents. These variants were identified through V3 peptide enzyme-linked immunosorbent assay screening and subsequent HMA analysis. The combination of these techniques represents a model for screening HIV variants within a large population.