POSITIONAL CLONING OF A GENE INVOLVED IN THE PATHOGENESIS OF TREACHER-COLLINS SYNDROME

Treacher Collins syndrome is an autosomal dominant disorder of craniof acial development, which has been localized to chromosome 5q32-33.1. I n the present study, the isolation of new polymorphic markers has allo wed the identification of overlapping recombination events in two affe cted individuals. Extension of the transcription map of the critical r egion proximally has resulted in the isolation of a new gene (which ha s been named Treacle) of unknown function. The identification of diffe rent mutations in five unrelated families, all of which would result i n premature termination of the predicted protein, indicates that the T reacher Collins syndrome gene has been positionally cloned.