A controlled family history study of Tourette's syndrome, III: Affective and other disorders.

In a family history study, the frequency of affective disorders was significantly higher for all relatives of Gilles de la Tourette's syndrome (TS) patients than for all relatives of controls. Among the relatives of TS patients, the presence of any behavior disorder was significantly more frequent for first-, second-, and third-degree relatives and total relatives. Among all relatives, 30.6% of the relatives of TS patients versus 6.1% of control relatives (p less than .0001) had some behavior disorder. Studies of first-degree relatives suggest that among those individuals expressing the Gts gene as some type of behavioral problem, about half have tics and half do not. These observations suggest that in addition to tics that Gts gene(s) can be expressed as a spectrum of behavioral disorders.