RESUMO
We report the first complete nucleotide sequence of an adult T cell leukaemia virus/human T cell leukaemia virus type I (ATLV/HTLV) isolate from a British patient of Caribbean origin. Sequence comparisons of our proviral clone (HS-35) with other molecular clones are shown. We note the strong sequence conservation between isolates of Caribbean and Japanese origin (2.3 percent divergence), but demonstrate the higher homologies existing between isolates originating from similar geographical areas (approximately 1 percent divergence). Implications for the origin, evolution and dissemination of the ATLV/HTLV-I subgroup are discussed. Analysis of defective proviral clones isolated from the same genomic library is also reported,and suggests a pattern of proviral sequence deletions during the biogenesis of defective proviruses. (AU)