A comparison of the genomes of capripoxvirus isolates of sheep, goats, and cattle

Abstract

HindIII, PstI, AvaI, and SalI sites were mapped on the genomes of six isolates of capripoxvirus from sheep, goats, and cattle. Genome pairs were aligned by the alignment of cross-hybridizing HinIII fragments and the introduction of padding fragments (pads) at specific locations. The majority of these pads represent the approximate positions of relative deletions or insertions. Three possible phylogenetic networks were generated for seven capripoxvirus isolates by Wagner parsimony analysis of the nonconserved HindIII sites on their genomes, and confidence limits were calculated for the network nodes. Nucleotide sequence divergence values, calculated from the numbers of nonconserved HindIII, PstI, AvaI, and SalI sites on the genomes of typical sheep, goat, and cattle isolates, indicated that the typical sheep and cattle isolates are more closely related to one another than to the typical goat isolate. Nonconserved HindIII, PstI, AvaI, and SalI sites were shown to be distributed throughout the genomes. Evidence that isolates YG-1 and OS-1 are descended from an isolate whose genome arose by recombination is discussed. Terminally repeated regions were identified on each of the capripoxvirus genomes mapped here. By mapping BamHI, ClaI, EcoRI, HindII, HindIII, and SalI sites present within the terminal 10 kb of the genome of isolate InS-1, the terminal repeats of this genome ware shown to be between 2.25 and 3.40 kb in length and inverted with respect to one another.