Complete genome sequencing and genetic analysis of canine distemper virus PS strain

To sequence the full genome of canine distemper virus(CDV) PS strain and to study the genetic variation and molecular features of the PS strain,10 fragments of the full length genome of CDV PS strain were amplified by RT-PCR,cloned into the pMD18-T vector and sequenced.The homology and evolutional relationship of CDV genome with reference strains were analyzed with DNAStar and Mega4.0 software.Sequence analysis showed that the complete genome was 15 690 bp in length with some amino acid site mutated.The homology analysis showed that the PS strain had a 97.9% similarity with MKY-KM08 strain,and 93.0% to 97.0% with other strains.The PS strain had a similarity of 93.2% and 93.0% with CDV3 and Onderstepoort vaccine strains,respectively.Phylogenetic analysis showed that all CDV strains included vaccine strain and wild strain.PS strain and MKY-KM08 strain both belonged to Asia-1 wild strain.The results indicated that the genome sequence of the PS strain had highest similarity with that of the MKY-KM08 strain,and it was a wild strain.