INVOLVEMENT OF HUMAN T-LYMPHOTROPIC VIRUS TYPE-I IN HUMAN NEOPLASIA

Of 211 human tissues analyzed by PCR-SSCP and direct sequencing for HT LV-I genes, 165 (78.2%) gave positive signals. Signals detected in fam ily members of adult T cell leukemia (ATL) patients showed mutations d istinct from those in ATL. HTLV-I gene sequences showed variability in same persons examined at different times. Lymphocytes with prototypic HTLV-I genes showed higher sister chromatid exchange following MNNG t reatment than those without. Nasopharyngeal carcinomas carrying both H TLV-I and Epstein-Barr virus genes showed markedly abnormal gene produ ct expression. HTLV-I genes in human DNA may cause deregulation of hos t cell genes upon exposure to carcinogens including viruses.