Analysis of Amino Acid 530 and 549 of Hemagglutin Gene in Two Canine Distemper Virus Strains

Canine distemper virus (CDV) is prevalent among domestic dogs and causes disease in various types of carnivores worldwide. In the present study, the genotype of two CDV strains, namely, ZJJ-SD and ZJJ-LN, were investigated based on the whole hemagglutininatinine (HA) antigen gene. The CDV strains were obtained from two foxes in Shangdong province and Liaoning province of China in 2011. Before now phylogenic analysis had been carried out for only 260 CDV strains, worldwide and an analysis was performed in the amino acid substitutions at positions 530 and 549 of the HA protein. Phylogenetic analyses revealed that the two strains, ZJJ-SD and ZJJ-LN, belonged to the CDV Asia I lineage. Site 530 of HA protein was found to be relatively conserved within CDV lineages in different host species by combining the genetic sequence data with the published data from 260 CDV strains worldwide. The data analysis showed a bias toward the predicted substitution Y549H for the non-dog strains in Asia I and Europe lineages. The strain ZJJ-SD, from wild canid, has a Y549H substitution. It is one of three Y549H substitution for wild canids in Asia I lineages.