J Vet Sci.  2002 Mar;3(1):31-39.

Genetic characterization of porcine circovirus-2 field isolates from PMWS pigs

• Kim JH
• Lyoo YS

Abstract

PMWS is a new emerging disease in swine herds worldwide. Field isolates of PCV-2, a putative major causative agent of PMWS, were isolated and genetically characterized. Viral genome of two field isolates (PC201DJ and PC201SS) from pigs showing typical PMWS was sequenced. The nucleotide sequence homology with other PCV-2 isolates was ranging from 95% to 99% in complete viral genomic sequence. The highly conserved nonanucleotide motif of replication origin was identical to that of other PCV-2 isolates. To determine the genetic heterogeneity of PCV-2 isolates, the phylogenetic tree based on the complete genome of PCV-2 isolates were constructed. Two PCV-2 field isolates were closely related to Canadian isolates of PCV-2. PCV-2 isolated from field may have an origin of North America and is possibly originated from importation of breeding stocks. The result indicates that although the genome of PCV-2 is relatively stable in general, minor genetic variations exist among PCV-2 isolates from the different geographic locations. These differences of viral genome might have an important implication for genetic characteristics of PCV-2 infection. Three major immunorelevant epitopes of capsid protein showed variations in amino acid sequences. Also, the variance of amino acid sequence in antigenic epitope existed between two Korean PCV-2 isolates.

Keyword

porcine circovirus; replication origin; sequence homology; phylogenetic tree; epitope

MeSH Terms

Animals
Base Sequence
Circoviridae Infections/*veterinary
Circovirus/classification/genetics/*isolation & purification
Cloning, Molecular
Conserved Sequence
DNA Primers
Genome, Viral
Korea
Molecular Sequence Data
Phylogeny
Polymerase Chain Reaction
Restriction Mapping
Sequence Alignment
Sequence Homology, Nucleic Acid
Swine
Swine Diseases/*virology
Wasting Syndrome/*veterinary/virology
Weaning