Abstract
The symptom characteristics of two Tourette's syndrome (TS) subgroups formed on the basis of their parents' obsessive-compulsive (OC) symptomatology were explored. TS subjects with parents having OC symptoms had significantly more OC symptoms and complex tics and a later age of symptom onset than the balance of the TS cohort. These findings suggest an association between parental OC symptoms and OC symptoms in their TS offspring.