Lack of homology among potexvirus RNAs

Representative cDNAs prepared against each of five different potexvirus RNAs were annealed to these and other viral RNAs to assess the extent to which these viruses might be related. In all cases, the cDNA hybridized to completion with its homologous RNA but failed to cross-hybridize significantly to any other viral RNA. Partial hybridization was detected when the cDNA of one virus was annealed to the RNA of a distinct strain of the same virus. We conclude that despite their morphological similarities, members of the potexvirus group have diverged substantially in nucleotide sequence.