The Exofish track shows regions of homology with the pufferfish Tetraodon nigroviridis. This information was provided by Olivier Jaillon and Hugues Roest Crollius at Genoscope. For further information and other Exofish tools please visit the Genoscope Exofish web site, or email exofish@genoscope.cns.fr. The following paper also describes exofish: 'Estimate of human gene number provided by genome-wide analysis using Tetraodon nigroviridis DNA sequence' Nature Genetics volume 25 page 235, June 2000.