Genetic Research and Studies for Tourette Syndrome

Recent research by Doctor Matthew State at Yale University suggests that Tourette Syndrome may be caused by an inversion defect on chromosome 13 of gene SLITRK1. This means that Tourette Syndrome can be inherited or caused by mutation. However, this research appears to apply to a very small minority of cases (1 - 2 %), and studies to locate all of the genes implicated in Tourette's syndrome are ongoing.

Other genetic studies indicate tic disorders, including TS, are inherited as a dominant gene(s) that may produce varying symptoms in different family members. A person with TS has about a 50% chance of passing the gene(s) to one of his/her children. However, the gene(s) may express as TS, as a milder tic disorder, or as obsessive compulsive symptoms with no tics at all. It is known that a higher than usual incidence of milder tic disorders and obsessive compulsive behaviors are more common in the families of TS patients. The sex of the child also influences the expression of the gene(s). The chance that the child of a person with TS will have the disorder is at least three times higher for a son than for a daughter. Yet only a minority of the children who inherit the gene(s) will have symptoms severe enough to ever require medical attention. In some cases, TS may not be inherited; these cases are identified as "sporadic" TS because a genetic link is missing.