Vertebrate DM domain genes encode a novel group of proteins related to the Drosophila doublesex and Caenorhabditis elegans mab-3 transcription factors. It is shown here that the recently identified gene, DMRT3, has a restricted embryonic expression profile that is conserved in chicken and mouse embryos. DMRT3 is expressed primarily in the forebrain, neural tube and nasal placode of both species. In the chicken, DMRT3 is also expressed in newly forming tail somites at early developmental stages and, later, in the Müllerian ducts of the urogenital system.