Tourette Syndrome

Biology Research Project

Definition of Tourette's Syndrome

I chose this genetic disease to clear up misconceptions people have about Tourette's. Tourette syndrome (TS) is a neurological disorder characterized by repetitive, stereotyped, involuntary movements and vocalizations called tics. Most people tend to have more tics in early childhood, and tend to get better in late teens onward, some tend to end up losing the disease. Although when most people think of Tourette's, they think of people swearing a lot of the time, though this isn't exactly true, because only about 6-12% of people who have been diagnosed with Tourette's have this form.


Tics are classified as either simple or complex. Simple motor tics are brief sudden movements that involve a limited number of muscle groups such as

  • blinking rapidly, shoulder shrugging, or head/shoulder jerking
  • Simple vocalizations might be repetitive throat clearing, sniffing, or grunting.

Complex motor tics have a distant coordinated patterns of movements involving several muscle groups such as

  • facial grimacing along with jerking the shoulders

Some motor tics might actually appear purposeful, like sniffing or touching objects, while some of the more complex vocal tics might even be entire phrases.

The Tourette Syndrome

Causes of TS

Although the cause of TS is unknown, current research points to abnormalities in certain brain regions (including the basal ganglia, frontal lobes, and cortex), the circuits that interconnect these regions, and the neurotransmitters (dopamine, serotonin, and norepinephrine) responsible for communication among nerve cells. Given the often complex presentation of TS, the cause of the disorder is likely to be equally complex.

Is TS inherited?

Evidence from twin and family studies suggests that TS is an inherited disorder. Although early family studies suggested an autosomal dominant mode of inheritance, more recent studies suggest that the pattern of inheritance is much more complex. Although there may be a few genes with substantial effects, it is also possible that many genes with smaller effects and environmental factors may play a role in the development of TS.


Because tic symptoms often do not cause impairment, the majority of people with TS require no medication for tic suppression.However, effective medications are available for those whose symptoms interfere with functioning. Neuroleptics (drugs that may be used to treat psychotic and non-psychotic disorders) are the most consistently useful medications for tic suppression; a number are available but some are more effective than others (for example, haloperidol and pimozide).


Most patients are diagnosed with TS after a year of motor and vocal tics. There are no blood, laboratory, or imaging tests needed for diagnosis. Although In rare cases, neuroimaging studies, such as magnetic resonance imaging (MRI) or computerized tomography (CT), electroencephalogram (EEG) studies, or certain blood tests may be used to rule out other conditions that might be confused with TS when the history or clinical examination is atypical.
National Geographic - Taboo - T.8 - Episode 4 (Only the Tourettes Part)