![](http://up.wiki.x.io/wikipedia/commons/thumb/b/b4/Hemagglutinin-alignments.png/260px-Hemagglutinin-alignments.png)
Sequence alignment of 27 H9N2 avian influenza hemagglutinin protein sequences. The top section is colored by residue conservation and the bottom by residue chemical properties. Alignment produced with ClustalW.
Photo credit: Opabinia regalis
Photo credit: Opabinia regalis