Autosomal dominant gene transmission in a large kindred with Gilles de la Tourette syndrome.

A multiplex kindred ascertained through a single proband with GTS has been systematically investigated with standardised diagnostic instruments for other cases of GTS and related disorders. Complex segregation analysis supported the hypothesis that a single major gene inherited in autosomal dominant fashion but with incomplete penetrance contributed most of the variance in the liability to develop GTS and related disorders. This result is consistent with previous segregation analyses which have employed different methods of ascertainment, and tends to confirm that a proportion of GTS is due to a dominant gene and is suitable for investigation with genetic markers for linkage analysis.