Chromosomal locations of duplicate genes in zebrafish and Tetraodon. Each box on the grids contains the number of duplicated genes (see Methods) shared between the indicated chromosomes. Boxes with large numbers denote chromosome pairs containing many duplicated genes. (A) Zebrafish-zebrafish comparison. (B) Tetraodon-Tetraodon comparison. The distribution of clusters of duplicated genes is highly nonrandom (for details, see text), indicating that most duplicated genes in these species are found on pairs of duplicated chromosomal segments. Map positions for zebrafish genes were derived from this work, and those of Tetraodon were obtained from http://www.ensembl.org/Tetraodon_nigroviridis/.
