Epidemiology and Infection


Development of a PCR system for porcine cytomegalovirus detection and determination of the putative partial sequence of its DNA polymerase gene

B. F. WIDEN a1c1, J. P. LOWINGS a1, S. BELAK a1 and M. BANKS a1
a1 Virology Department, Central Veterinary Laboratory/Veterinary Laboratories Agency, New Haw, Addlestone, KT15 3NB, United Kingdom


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.

(Accepted April 22 1999)

c1 Author for correspondence.