Cloning and characterization of BK virus-related DNA sequences from normal and neoplastic human tissues

DNA homologous to that of the known papovarius BK was cloned from the high molecular weight DNA of two human tissues: a normal liver and a kidney carcinoma. The clone isolated from human liver consisted of DNA indistinguishable from prototype BK by restriction enzyme analysis that used ten different enzymes. The DNA cloned from the human carcinoma of the kidney was subject to rearrangement in recombination-deficient bacteria, and exhibited a deletion of a small segment of DNA localized to the BK late region. Restriction fragments representing the BK origin and promoter regions are overrepresented in the tumor-derived clone. The possible significance of retrieval of defective viral genomes from tumor tissues is discussed.