Phylogenetic relationships among rho (a, b) and concatenated synteny (c, d) sequences. Amino acid (a, c) and RY-coded DNA (b, d) sequence-based trees are shown. Numbers attached to teleostean gene IDs denote syntenies on which genes are encoded. Numbers beside branches indicate local bootstrap  support (%) of each branch. * Chicken and human rho sequences of synteny data are from a remote locus.