After PCR amplification with conservative cytomegalovirus primers, a 520 nucleotide putative
partial sequence of the DNA polymerase gene of porcine cytomegalovirus (PCMV) was
determined. Sequence comparison revealed homology to DNA polymerase genes from various
beta herpes viruses and a dendrogram was constructed depicting the relationship of PCMV to
other members of the Herpesviridae family. The dendrogram indicates that PCMV is indeed a
beta herpes virus that is more closely related to human herpes virus types 6 and 7 than to
type 5.
To address the difficulties encountered during conventional PCMV detection and
characterization a set of nested PCR primers were constructed which generated DNA
fragments of 415 and 257 bp from the DNA polymerase gene. The nested PCR system proved
specific for PCMV and provided a novel means for the detection of this poorly characterized
herpes virus in pig populations, vaccines and in organs used in xenotransplantation.