Objective: To understand the gene characterization of hamagglutinin (HA) of AIV H5N1 subtype originated from the pan Pacific regions in order to find out its mutation possibility.
Methods: 50 HA gene sequences originated from pan Pacific regions were downloaded, including Thailand, Vietnam, Hong Kong, Indonesia, mainland of China, Mongolia and Russia, the alignments of nucleic acid and amino acid sequence of HA gene were analyzed, and the phylogenetic relationships among 50 H5N1 high pathogenic avian influenza (HPAI) virus were evaluated by bio-software DNASTAR 5.0 and MEGA 3.1.
Results: 50 HPAI viruses were separated into 3 clusters, including Thailand and Vietnam cluster, China-Indonesia-Northern Asia cluster and the other cluster primary composed by isolates from 1996 to 2001 similar with Gs/Gd like or the other in the respect of genetype. The analysis of HA molecular characterization shows that the isolates from Thailand and Vietnam could have the similar antigenic profiles, while the others could have different molecular characterizations especially in the respect of epitope determinant sites, besides the similarity in a certain zones.
Conclusion: Hamagglutinin characterization of HPAI virus originated from the pan Pacific regions could show zone specificity, as well as with the similarity in a certain range.