Electrophoretic profiles of DNA amplicons obtained by single PCR with genomic DNA extracted from CsCl gradient-purified PCV-1. The six primer pairs used to amplify ORF1 of the PCV-1 strain yielded DNA amplicons of the expected size. Lane 1, primers ORF1.PCV1.S1 and ORF1.PCV1.AS5 (865 bp); lane 2, primers ORF1.PCV1.S2 and ORF1.PCV1.AS5 (830 bp); lane 3, ORF1.PCV1.S1 and ORF1.PCV1.AS2 (500 bp); lane 4, primers ORF1.PCV1.S1 and ORF1.PCV1.AS1 (415 bp); lane 5, primers ORF1.PCV1.S2 and ORF1.PCV1.AS2 (465 bp); and lane 6, primers ORF1.PCV1.S2 and ORF1.PCV1.AS1 (375 bp); lane L, 1-kb DNA ladder.