Tourette Syndrome

Tourette Syndrome

Tourette's is thought to involve faulty regulation the brain circuits between the frontal cortex and the basal ganglia. Studies have established with little doubt that Tourette's syndrome is genetic, but the exact type of inheritance is debatable. Tourette's syndrome was thought to be transmitted by means of an autosomal dominant gene. Recent studies suggest that the method of transmission may be more complex then thought. More than one gene may be involved, and it' is possible that different genetic effects are involved in different families. Another aspect is that you don't "inherit" Tourette's syndrome. You inherit a genetic predisposition or vulnerability to the condition. It is a condition of variable penetrance, which means that not everyone who inherits the gene will express severe symptoms.

Accurate figures are hard to come by because good broad-based population studies have not been done. Since tics tend to subside as children mature, fewer adults have Tourette's, and population estimates adults may underestimate the prevalence rates in children. Another complication in prevalence estimates is that most mild Tourette's syndrome may never come to diagnostic attention. A 2001 study by Kurlan indicated that "over 19% of children in regular education classes have tics and almost 4% of children in regular education meet diagnostic criteria for Tourette's Syndrome.

Tourette syndrome is a neurological disorder characterized by repetitive, stereotyped, involuntary movements and vocalizations called tics. (http://www.ninds.nih.gov/disorders/tourette/detail_tourette.htm) The disorder is named after Dr. Georges Gilles de la Tourette, a French neurologist who in 1885 first described the condition in an 86-year-old noblewoman.

There are no clinical or medical tests for definitively ruling in or out Tourette's syndrome. The diagnosis is made based upon a history of persistent, frequently-changing motor and vocal tics which develop during childhood. Other factors must be ruled out before conferring a diagnosis of Tourette syndrome, so physicians may do some screening tests or other medical testing, just to rule out other conditions if they are suspected.

Tics are classified as either simple or complex. Simple motor tics are sudden, brief, repetitive movements that involve a limited number of muscle groups. Some of the more common simple tics include: eye blinking and other vision irregularities, facial grimacing, shoulder shrugging, and head or shoulder jerking. Simple vocalizations might include: repetitive throat-clearing, sniffing, or grunting sounds. Complex tics are distinct, coordinated