Figure 3: Conserved syntenies between platyfish and medaka.

(a) The medaka orthologs of genes on X. maculatus chromosome 9 (Xma9) tend to lie on Oryzias latipes chromosome 4 (Ola4), showing that the genic content of these chromosomes has remained intact with no translocations in the 120 million years since the lineages of these species diverged. Each gray dot along the horizontal axis labeled Xma9 represents the position of a platyfish gene whose medaka ortholog (as judged by reciprocal best-BLAST hit analysis) lies directly vertical to the Xma9 gene, plotted on the appropriate medaka chromosome¹⁰. (b) Reciprocally, nearly all of the platyfish orthologs of genes on medaka chromosome Ola4 lie on Xma9. (c) Nearly all of the medaka orthologs of Xma19 lie on Ola22, except for a segment about 1 Mb long at position 20 Mb on Ola22 that appears on Ola24 (dashed box).