Q: Is it inherited?

A: Genetic studies indicate tic disorders, including TS, are inherited as a dominant gene that may produce varying symptoms in different family members. A person with TS has about a 50% chance of passing the gene to one of his/her children. However, that gene may express itself as TS, as a milder tic disorder, or as obsessive/compulsive symptoms with no tics at all. It is known that tic disorders and obsessive/compulsive behaviors are more common in families of TS patients then in the general population.

The sex of the child also influences the expression of the gene. 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. In some cases, TS may not be inherited; these cases are identified as "sporadic "TS because a genetic link cannot be found.