Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: November 10, 1997
Publication Date: N/A
Technical Abstract: To gain more insight into the genetic relationships between 6 different canine coronavirus (CCV) strains, the variable region of the spike protein gene was sequenced. The CCV strains were: 2 ATCC reference strains, a vaccine strain, the NVSL challenge strain, and 2 original field isolates. By reverse transcription-polymerase chain reaction analysis, all 6 strains were shown to contain ORF 7b, and thus, none were TGEV-like since TGEV viruses lack an ORF 7b. By sequence analysis of the variable 900 nucleotides at the immediate 5' end of the spike protein gene, 5 of the 6 CCV strains had a high degree of homology with FIPV. However, one CCV field isolate was different and had a high degree of homology with the 5' end of the TGEV spike protein gene. This suggests that RNA recombination has occurred at this site between antigenically related coronaviruses. These marked differences in the spike protein may account for the biological variation amongst CCVs.