Genotypic variation among six isolates of lactate dehydrogenase-elevating virus.

In the present study, six lactate dehydrogenase-elevating virus (LDV) isolates obtained independently from inbred mice were compared by RNA oligonucleotide fingerprint analysis. The genome RNAs of four of the isolates gave unique fingerprint patterns. The patterns obtained for the other two isolates were similar, but not identical to one of the four unique patterns. These results indicate that more than one genotype of LDV exists and that virus isolates can be grouped by genotype. We have also demonstrated the presence of a 3'-terminal poly(A) tract by direct sequencing of 3'-32P-labelled LDV genome RNA. The presence of a 3'-terminal poly(A) tract distinguishes LDV from the members of the family Flaviviridae, which lack a 3'-poly(A), and justifies the current classification of LDV within the family Togaviridae.