This project is a continuation of past efforts to map one or more genes responsible for Tourette Syndrome through linkage analysis. To date, linkage mapping efforts have focused on relatively large families with Tourette Syndrome (TS). This approach relies heavily on correct diagnosis of all family members. However, the wide range of expressivity of GTS genes within families and the difficulty in distinguishing mildly affected individuals from unaffected individuals make accurate diagnosis of all family members problematic. In contrast, family members with full blown Tourette Syndrome are relatively easy to diagnose. Patch mapping utilizes only clearly affected individuals within families. DNA from the affected individuals is analyzed using dense sets of polymorphic markers distributed evenly throughout all the chromosomes. The longest chromosomal segments (or patches) shared among the affected individuals are likely to encompass GTS genes. Efforts during this grant year will involve a small scale test of patch mapping using five clearly affected individuals from a large Wisconsin family. A second goal in this grant year will be to bank DNA samples which are collected worldwide through TSA sponsored programs. Special emphasis will be place on DNA samples from nuclear families suitable for a form of linkage mapping called sib pair analysis. The banked DNA will be made available to the TSA Consortium for genetics. James L. Weber, Ph.D. Marshfield Medical Research Foundation, Marshfield, WI Award $6,531 Tourette Association of America Inc. – Research Grant Award 1994