[Molecular-genetic characteristic of HIV-1 A and B subtypes variants isolated in Novosibirsk region].

AIM: Study phylogenetic interconnections of HIV-1 subtype A and B variants circulating in Novosibirsk region (NSR).

MATERIALS AND

METHODS

268 HIV-1 variants isolated in 2007 - 2010 from blood samples of HIV infected patients in NSR, Samara, Congo and Moscow. HIV-1 variant genotyping was performed by analysis of 1.3 kb long pol gene nucleotide sequences. Phylogenetic analysis of nucleotide sequences was carried out by program Mega version 4.1 by constructing phylogenetic trees by nearest neighbor method. Nucleotide distances were calculated by Kimura method.

RESULTS

The studied HIV-1 subtype B variants form separate phylogenetic groups with a low HIV-1 nucleotide sequence homology level combined based on territorial principle and/or time of HIV infection in a territory but not possessing interconnection with a specific population risk group. Subtype A HIV-1 is a fairly homogenous monophyletic group. Phylogenetic differences during studies of HIV-1 isolated from risk group patients - injection drugs users and individuals infected through sexual contacts were not detected. HIV variants isolated from patients infected in Moscow and Samara generally grouped with HIV variants circulating in the European part of Russia.

CONCLUSION

An independent circulation of genetically separate HIV-1 subtype B groups is observed on the territory of siberian region which is a result of multiple independent introductions of distant variants of the virus. The confirmed limited spread of this HIV-1 genetic variant with a subsequent territorial separateness creates a possibility of formation of genetically different virus populations. The studies of subtype A viruses performed confirm the high level of homogeneity detected earlier in other Russia territories of HIV-1 belonging to this genetic variant. Monophyly of subtype A HIV variants is explained by imposition of 2 factors - territorial mobility of the population inside the country and lack of specific transmission routes for HIV-1 subtype A.