An encyclopedia of mouse genes

The laboratory mouse is the premier model system for studies of mammalian d evelopment due to the powerful classical genetic analysis(1) possible (see also the Jackson Laboratory web site, http://www.jax.org/) and the ever-exp anding collection of molecular tools(2,3). To enhance the utility of the mo use system, we initiated a program to generate a large database of expresse d sequence tags (ESTs) that can provide rapid access to genes(4-16). Of par ticular significance was the possibility that cDNA libraries could be prepa red from very early stages of development, a situation unrealized in human EST projects(7,12). We report here the development of a comprehensive datab ase of ESTs for the mouse. The project, initiated in March 1996, has focuse d on 5' end sequences from directionally cloned, oligo-dT primed cDNA libra ries. As of 23 October 1998, 352,040 sequences had been generated, annotate d and deposited in dbEST, where they comprised 93% of the total ESTs availa ble for mouse. EST data are versatile and have been applied to gene identif ication(17), comparative sequence analysis(18,19), comparative gene mapping and candidate disease gene identification(20), genome sequence annotation( 21,22), microarray development(23) and the development of gene-based map re sources(24).