Zebrafish genetics and its implications for understanding vertebrate development.

The identification of genes via their mutant phenotypes is the most direct way of dissecting the molecular basis of developmental processes. While this approach has been extremely powerful in invertebrates such as Drosophila and Caenorhabditis elegans, it has until recently been lacking in vertebrates. Now two landmark studies by the groups of Nüsslein-Volhard and Driever have for the first time provided the basis for a comprehensive genetic dissection of vertebrate development using the teleost fish, Danio rerio. The mutations identified in these screens look set to revolutionise our understanding of vertebrate development.