A Case of Down Syndrome with Tourette Syndrome

Background Tourette syndrome, first described in 1885, is a tic disorder differentiated from other movement disorders, such as myoclonic movements or transient tics of childhood. The median age at onset is seven years. In some cases, remissions occur or symptoms diminish. In other cases, the condition is lifelong. DSMIII-R diagnostic criteria are: multiple motor and one or more vocal tics present at some time; tics that occur many times a day (usually in bouts), nearly every day or intermittently throughout a period of more than one year; the anatomic location, number frequency, complexity, and severity of the tics change over time; onset before age 21; occurrence not exclusively during psychoactive substance intoxication or known central nervous system disease. Since identical twins tend to be concordant, while siblings and fraternal twins are usually discordant for the syndrome, the hypothesis that the disorder has a genetic basis has been examined. Pauls and Leckman (1986) suggest that Tourette syndrome is etiologically related to chronic tics and also to obsessive-compulsive disorder, and is inherited as a "highly penetrant, sex-influenced, autosomal dominant trait." Donnai (1987) has presented evidence that the gene location suggested by Comings (Comings et al, 1986), 18q22.1, is correct. Her patient's karyotype revealed a deletion at 18q22.2. Prevalence of Tourette has been estimated at 1/2000 for total manifestations of the syndrome to 1/200 or 1/300 for multiple tics (Licamele and Goldberg, 1988). Treatment of genetic disease that corrects the abnormal gene or introduces the lacking enzyme constitutes a cure and may be possible in certain inborn errors of blood formation by means of bone marrow transplant. Organ transplants have also been