Characterization of a C-type retrovirus isolated from an HIV infected cell line: complete nucleotide sequence.

As previously reported, a C-type retrovirus, referred to as retrovirus X was isolated from HIV infected cells. In order to further characterize this virus, the proviral DNA was cloned and sequenced. The organization of the genome (8379 bp) appeared to be typical of the mammalian type C retroviruses. The virus was shown to be closely related to the gibbon ape leukaemia virus (GALV) with 87% similarity when the sequence was compared with the published genome of the Seato strain of GALV. At the level of the long terminal repeat where comparison was possible with other strains, the closest relationship was found with the San Francisco strain of GALV and with the simian sarcoma virus. These results suggest that the isolate should be considered as a strain of GALV.