Nucleotide and Amino Acid Sequence Analysis of Hemagglutinin Protein in Cleavage Site Region of H9N2 Isolated from Broilers in Tehran Province during 1998-2007

Iranian poultry industry has been affected by Avian Influenza (AI) virus Since 1998, subtype H9N2. The association of high mortality and case report of H5N1 and H9N2 influenza virus in wild birds in recent years raised the specter of a possible new genetic modified AI virus. Partial nucleotide sequences and deduced amino acid of Hemagglutinin (HA) genes in cleavage site region of 9 H9N2 influenza viruses isolated from broilers in Tehran Province during 1998-2007 were genetically analyzed. The isolates possessed two types of amino acid motif R S S R/G L and R S N R/G L - at the cleavage site of HA. " R S N R/G L in Iranian isolates is the same as the motif previously reported in Israel. The results of this study indicated that all of Iranian viruses have potential for emerging for highly pathogen influenza virus, thus continuously monitoring of viruses is essential in Iran.