Evolution of the silver genes in vertebrates. (a) Maximum-likelihood phylogeny of Silver protein sequences based on 523 AA positions. The repeat region  was excluded from the alignment. The tree was rooted with human GPNMB. Numbers at the branches denote bootstrap values (maximum likelihood/neighbor joining) above 50%. (b) Synteny of silv-containing regions in vertebrate genomes. The human SILV region is syntenic to two silv paralogons in Tetraodon (Tni), stickleback (Gac), medaka (Ola) and zebrafish (Dre). Numbered bars represent genes contributing to conserved synteny, genes that do not contribute to conserved synteny are not shown. Blue bars indicate genes that are duplicated along with silv. Dotted lines connect orthologous genes.