Full-length characterization and phylogenetic analysis of hemagglutinin gene of H9N2 virus isolated from broilers in Iran during 1998–2007

摘要: H9N2 avian influenza A viruses (AIV) have become panzootic in Eurasia over the last decade and are endemic Iran since 1998, inactivated vaccine has been used chickens to control disease. The hemagglutinin (HA), one of eight protein-coding genes, plays an important role during early stage infection. To study their evolution zoonotic potential, we conducted silico analysis that infected broiler Tehran Province, between 1998 2007. complete coding region HA genes from nine subtypes isolated chicken flocks Province 1998–2007 was amplified sequenced. Sequence phylogenetic studies subtype on basis data 9 this 30 selected strains available GenBank. analyses revealed a large number similar substitution mutations close evolutionary relation among sequences HA. isolates possessed two types amino acid motif –R–S-S-R/G-L- -R-S-N-R/G-L- at cleavage site results showed all representative belong low pathogenic AIVs none basic required for highly (R-X-R/K-R). Six out these leucine position 226, which prevails found human strains. Phylogenetic our belonged G1-like sublineage. Also, some degree homology with other isolates, e.g., 89.46–93.93.39% qu/HK/G1/97 93.39–98.39% pa/Narita/92A/98. evidence indicates H9 virus circulating past years were not well conserved. Our finding emphasizes importance reinforcing AIV surveillance, especially after emergence high pathogenicity poultry Iran.