Determination of natural host taxonomy of RNA tumor viruses by molecular hybridization: application to RD-114, a candidate human virus.

The lysogenic bacteriophages and the RNA tumor viruses have in common the ability to add their genetic information to the genome of their host cells. The biological similarity extends further; data summarized here indicate that they both possess homology to the DNA of their uninfected indigenous hosts. Sharing of common sequences with normal host DNA has been established with avian, murine, feline, and primate oncornaviruses. This finding provides a method for determining the taxonomic position of the natural host of any new RNA tumor virus isolated. Application of this approach to RD-114 revealed extensive hybridization to normal cat DNA and little, if any, hybridization to human DNA. We conclude that the data assign a feline origin rather than a human origin to RD-114.