Phylogenetic relationships among the histone H2A.Z family from different eukaryotes. The phylogeny reconstruction was carried out using the minimum evolution (ME) method and the Close-Neighbor-Interchange (CNI) algorithm. The root of the tree is denoted in black and the numbers represent p-distance (see methods for details). The four new carp H2A.Z subtypes are indicated in red. The sequences of H2A.Z are listed in Additional file 5: Table S2. CNI, Close-Neighbor-Interchange; ME, minimum evolution.