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Simplified cladograms representing major lineages of the PB2 (A), PB1 (B), PA (C), NP (D), M (E) and NS (F). The cladograms are based on the phylogenetic trees shown in Figure 1–Figure 4. Major H5N1 genotypes are shown in blue text and prototype virus lineages are shown in red text. Lineage names are provided in the Figure 2 legend.
