Molecular relatedness of mammalian RNA tumor viruses as determined by DNA hybridization.

Each of six mammalian C-type viruses-including two feline leukemia viruses, three murine leukemia viruses, and the human "candidate" virus RD-114-can be distinguished from each other by hybridizing DNA synthesized by viral reverse transcriptase with viral RNA. Characterization of the DNA . RNA hybrids by hydroxylapatite chromatography revealed nucleotide sequence diversity among the viruses, detectable both by the amount of cross-hybridization and by the decreased thermal stability of heterologous hybrids.