NONRANDOM DELETIONS IN HUMAN FOAMY VIRUS LONG TERMINAL REPEAT DURING VIRAL-INFECTION

We have characterized a new form of human foamy virus (HFV) non-random deleted long terminal repeat (LTR) sizing 1078-bp, deleted in its U3 region, sensitive to the viral transactivator and functional in an inf ectious proviral clone. Besides two known HFV LTRs of 1260-bp and 1123 -bp, this LTR represents the smallest, designed S. Analysis of the LTR sequence shows the presence of short direct repeats surrounding the d eletions, suggesting a mechanism generating deletion by misalignment o f the growing strand during replication. Our data suggest that the del eted LTRs, preferentially associated with chronic viral infection, cou ld be related with viral persistence.