Figure 1. Phylogenetic tree for the hemagglutinin gene of influenza viruses constructed by neighbor-joining method. Sequences obtained in this study were labeled with a circle (EMA1/EMA2-2:6-R07 group) and triangle (EMA2 group). The remaining sequences can be found in GenBank. The numbers at each branch point represent bootstrap values, and they were determined by bootstrap analysis by using 1,000 replications. Scale bar = 0.01 nucleotide substitutions/site.
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