[Canine Circovirus Genome Cloning and Sequence Analysis].

Dog circovirus (DogCV) is a newly discovered mammalian circovirus. To investigate the genomic characteristics and genetic diversity of DogCV spreads in China, the first genome sequence of Chinese isolate, designated as JZ98/2014,was obtained by overlap PCR using the DNA extracted from dog serum as template for amplification. The nucleotide content and genome organization were subsequently analyzed. The results showed that the full-length genome of JZ98/2014 is 2063nt,and contains three major open reading frame: ORF V1 (encodes the 303 amino acid Rep protein),ORF C1(encodes the 270 amino acid Cap protein),and ORF C2(encodes 106 amino acids).JZ98/2014 shared 82.1%-89.5% homology with the complete genome sequences of DogCV isolates from America and Europe. The Rep gene and Cap gene of JZ98/2014 shared 82.1%-89.5%and 84.6%-89.1% homology, respectively, with the same genes from other DogCVs. Phylogenetic tree analysis indicated that there were several different genetic clades of DogCV spread in the world, and JZ98/2014 formed a clade by itself.