Divergent strain of Human T-Lymphotropic virus type 1 (HTLV-1) within cosmopolitan subtype in Argentina

EIRIN ME, DILERNIA D, BERINI C, JONES L, PANDO MA, BIGLIONE M

AIDS RESEARCH AND HUMAN RETROVIRUSES

Mary Ann Liebert, Inc

Año: 2008 vol. 24 p. 1237 - 1244

0889-2229

HTLV-1 Cosmopolitan subtype Transcontinental subgroup A has been described among aboriginal communitiesfrom the northwest endemic area of Argentina. Moreover, Transcontinental subgroup A and the Japanesesubgroup B were reported among blood donors from the nonendemic central region of the country. We carriedout the first HTLV-1 phylogenetic study in individuals residing in Buenos Aires capital city. Phylogeneticanalysis performed on the LTR region showed that all 44 new strains clustered within the Cosmopolitan subtype,with 42 (95.4%) belonging to Transcontinental subgroup A. Of them, 20 (45.5%) strains grouped in thelarge Latin American cluster and 4 (9.1%) in the small Latin American cluster. The majority of them belongedto individuals of nonblack origin, grouped with Amerindian strains. Three (6.8%) were closely related to SouthAfrican references and two monophyletic clusters including only HIV/HTLV-1 coinfected individuals were observed.Interestingly, two (4.5%) new sequences (divergent strains) branched off from all five known Cosmopolitansubgroups in a well-supported clade. In summary, these findings show that HTLV-1 Cosmopolitansubtype Transcontinental subgroup A is infecting residents of Buenos Aires, a nonendemic area of Argentina,and confirm the introduction of divergent strains in the country.