Zebrafish genetic map with 2000 microsatellite markers

The zebrafish is the first vertebrate organism used for large-scale genetic screens seeking genes critical to development, These screens have been qui te successful, with more than 1800 recessive mutations discovered that spea k to morphogenesis of the vertebrate embryo. The cloning of the mutant gene s depends on a dense genetic map. The 2000 markers we present here, using m icrosatellite (CA) repeats, provides 1,2-cM average resolution. One centimo rgan in zebrafish is about 0.74 megabase, so, for many mutations, these mar kers are close enough to begin positional cloning by YAC walks. (C) 1999 Ac ademic Press.