Tics and Tourette Syndrome (TS)

Etiology

Primary TS has a genetic basis, confirmed by its high prevalence in twins and families with one or more affected members. Genome scanning of sibling pairs and large pedigrees has identified several regions that may give rise or increase susceptibility to TS.15-17 To date, however, with a substantial percentage of the human genome having been excluded and relatively few cases being ascribed to a specific genes, i.e., SLTKR1, 18,19 the precise gene and mechanism of inheritance remain undetermined. A complex genetic mechanism is likely, perhaps one associated with multiple genes or an epigenetic effect, i.e., an environmental exposure influencing gene expression.