Tics associated with autistic and pervasive developmental disorders.

Coincident cases of Tourette syndrome and Pervasive Developmental Disorders increasingly have been reported in the literature. Coincident cases currently number around 90. A minority of cases have been associated with cases of Tourette syndrome and tics in other family members; this has led some authors to suggest that Tourette syndrome may be responsible for some of the genetic heterogeneity in Pervasive Developmental Disorders. The literature is reviewed, along with some aspects of the neurobiology of the two conditions with arguments for and against this hypothesis.