This proposal requests support for the 4th in a series of International Workshops on Mouse Genome Mapping to stimulate the exchange, integration and distribution of genetic information among scientists analyzing the mouse genome. The Genome Office of NIH sponsored a meeting of leading investigators in mouse genome mapping in November, 1989 at Princeton University to define a set of common goals for mapping of the mouse genome. A report was drafted from that meeting that addressed genetic and physical mapping of the mouse genome, the initiation of focused amounts of genome sequencing, the problem of informatics and the special nature of mouse genetic resources that facilitate the genome mapping work. The meeting proposed in this application will assist in the establishment of more formalized working groups and committees to insure the continuation of cooperative efforts for integrating information and database development on an international basis. The goals of this meeting will be to (1) discuss and evaluate the goals outlined in the Princeton report; (2) to integrate the genome mapping information into composite genetic and physical maps; (3) to evaluate physical mapping information and share mapping resources; (4) to examine the current status of large scale DNA sequencing technologies; (5) to evaluate mouse genome data bases, their accessibility and management; and (6) to formalize an international mouse genome organization that will sponsor future workshops and promote interaction among investigators in the mouse genome effort.