Genetic Analysis of Torque Teno Canis Virus Identified in Republic of Korea

SIMPLE SUMMARY: Torque teno viruses are small, ubiquitous viruses with highly diverse genomes and a wide host range. However, their incidence in dogs remains unknown in Republic of Korea. In this study, we detected Torque teno canis virus and performed whole-genome sequencing using canine fecal samples. This is the first study to determine the incidence of Torque teno canis virus in Republic of Korea and report a new recombinant virus. ABSTRACT: Torque teno canis virus (TTCaV) is an approximately 2.8 kb circular single-stranded DNA virus known to cause infections in dogs. However, its incidence in Republic of Korea remains unknown. In this study, 135 dog fecal samples were collected to determine TTCaV infection status in Republic of Korea. Based on polymerase chain reaction (PCR) analysis, 13 of 135 (9.6%) dogs tested positive for TTCaV. Three full-length genome sequences (GenBank IDs: MZ503910, MZ503911, and MZ503912) were obtained from the positive specimens. Phylogenetic tree construction and sequence identity, similarity plot, and recombination analyses were performed using these three full-length genomic sequences. Among the three full-length genomes, MZ503912 was determined to be a recombinant virus based on analysis with the reference TTCaV strains. This novel virus strain might have been generated by recombination between TTCaV strain KX827768 discovered in China and MZ503910 discovered in Republic of Korea. This is the first report to determine the incidence, genetic variation, and recombination of TTCaV in dogs in Republic of Korea. Further studies are needed to elucidate TTCaV pathogenesis in dogs.