F. Letourneur et al., COMPLETE NUCLEOTIDE-SEQUENCE OF AN AFRICAN HUMAN T-LYMPHOTROPIC VIRUSTYPE-II SUBTYPE-B ISOLATE (HTLV-II-GAB) - MOLECULAR AND PHYLOGENETIC ANALYSIS, Journal of General Virology, 79, 1998, pp. 269-277
We report the first complete nucleotide sequence of an African human T
-cell lymphotropic virus type II, This new strain, called HTLV-II-Gab
(Gab), was obtained from the uncultured peripheral blood mononuclear c
ells of a 44-year-old healthy Gabonese male who lived in a remote rura
l area, with neither history of blood transfusion nor sexual intercour
se with non-Africans, Using nested PCR, 25 overlapping fragments, repr
esenting the entire proviral genome, were obtained, cloned and sequenc
ed, The overall nucleotide sequence comparison with the four other ava
ilable complete HTLV-II genomes indicated that Gab was more closely re
lated to the HTLV-II subtype b prototypes (98.9, 99.3 and 98.2% nucIeo
tide similarity with G12, NRA and GU respectively) than to the subtype
a prototype (95.1% nucleotide similarity with Mo), Restriction profil
es studies and phylogenetic analyses confirmed that Gab was a subtype
b strain. However, this strain represents a newly described restrictio
n fragment length polymorphism subtype, closely related to one of the
rare partial ly sequenced African isolates originating from a pygmy li
ving in Cameroon (PYGCAM), Nevertheless, the very low genetic divergen
ce observed between this new African strain and the American strains r
aises several questions on the origins and level of genetic variabilit
y over time of this human retrovirus.