Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders, now available world-wide through the Internet. The catalog was authored solely by Dr. Victor McKusick for its first 35 years. His goal throughout the history of the catalog has been the production of a comprehensive, timely and authoritative compilation of the literature on human genes and genetic disorders. As map-based gene discovery is employed increasingly in many medical disciplines, the utility of OMIM as a genome resource has spread far beyond the boundaries of medical genetics. The current application proposes four specific aims for the next five years of OMIM: 1) Enhancement, restructuring and ongoing maintenance of the OMIM files, including the implementation of a new authorial and editorial organizational structure,a nd completion of the transition to a multi- authored and multi-edited test. 2) Service to the clinical and research genetics communities through enhanced accessibility of the resource, creation of "hot links" to related databases, and continued provision of consultation and technical assistance in the use of OMIM. 3) Dissemination of information concerning th availability, accessibility and potential use of OMIM for research, teaching and clinical practice. 4) Utilization of OMIM as a collaborative resource for medical genetics and genome research, including collaborative interactions of OMIM staff with scientists engaged in the dissemination of related genome information, as well as encouraging the utilization of OMIM for specific research applications by the genetics community.