Genetics & Research
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 behaviours 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 cannot be found.
Recently there has been more research aimed at understanding how the disorder is transmitted from one generation to the next and researchers are working toward locating the gene marker for TS. That focus has been enhanced by the efforts of an international group of scientists who have formed a unique network to share what they know about the genetics of TS. Additional insights will be obtained from studies of large families (kindreds) with numerous members who have TS. At the same time, investigators continue to study specific groups of brain chemicals to better understand the syndrome and to develop new and improved medications. Work is also ongoing to identify sub-groups of people with TS. If you would like to support this ongoing work we urge you to become a donor to assist with ongoing initiatives.
The Tourette Syndrome Foundation of Canada (TSFC) has a research fund named in honour of Dr. Mort Doran's immeasurable and unselfish contributions to the Tourette community and in perpetual recognition of these contributions and his dedication.
Learn more about the Mort Doran Research Fund.