Gene may be linked to Tourette’s syndrome

Researchers said on Thursday they have found a gene that contributes to the development of Tourette Syndrome, but that many other genes are also likely to be involved in the complex disorder.

Tourette Syndrome may affect as many as 1 in 100 people and is marked by muscle and vocal tics including repeated sudden movements or vocalizations. Children with Tourette Syndrome also often have Attention deficit hyperactivity disorder, Obsessive-Compulsive Disorder or Depression.

In a report published in this week’s issue of the journal Science, Dr. Matthew State of the Yale University School of Medicine and colleagues at several other institutions said a gene called SLITRK1 appears to contribute to some cases of Tourette Syndrome.

“This finding could provide an important clue in understanding Tourette’s on a molecular and cellular level,” State said in a statement. “Confirming this in even a small number of additional TS patients will pave the way for a deeper understanding of the disease process.”

State and colleagues looked for unusual patients with a clear genetic anomaly.

Tourette syndrome
Gilles de la Tourette syndrome, also called simply Tourette syndrome, is a disorder characterized by multiple motor and vocal tics that begins before age 18.

Causes, incidence, and risk factors
Tourette syndrome, first described by Georges Gilles de la Tourette in 1885, is a complex condition that arises during childhood or adolescence. It is characterized by repeated and involuntary body movements (tics). A tic is a sudden, rapid, stereotyped motor movement or vocalization. Tics can include eye blinking, repeated throat clearing or sniffing, arm thrusting, kicking movements, shoulder shrugging or jumping.
More information: Tourette’s Syndrome

They found a boy who was the only member of his family with Tourette Syndrome, and who had a gene inversion on chromosome 13. A gene inversion occurs when a section of chromosome appears to have broken off and flipped before being reinserted.

Looking at the ends of this section, the researchers found one gene, called SLITRK1, that is active in brain cells and is associated with the growth and interconnection of neurons.

Then they screened 174 more people with Tourette Syndrome, comparing their SLITRK1 gene to the version found in people who do not have the syndrome, and found a genetic mutation.

What is obsessive-compulsive disorder (OCD)?

Obsessive-compulsive disorder (OCD) is a psychiatric disorder characterised by obsessions and compulsions. Obsessions are persistent, “self generated” thoughts that cause you distress. However, compulsions are not inherently enjoyable and do not result in the completion of a useful task. Compulsions are repetitive acts you may perform in an attempt to reduce the distress.

OCD is an Anxiety disorder, a category that includes Post-traumatic Stress Disorder, Social Anxiety Disorder (social phobia) and Panic disorder.

OCD should not be confused with obsessive-compulsive personality disorder (OCPD). Despite its name, OCPD does not involve obsessions and compulsions. It is a personality pattern that involves being preoccupied with order, and traits such as perfectionism and inflexibility. Only a few people with OCD have OCPD.
More information: Obsessive-Compulsive Disorder

This one gene variation is unlikely to hold all the answers to Tourette Syndrome, State said.

“I think there is general consensus at this point that there are likely to be multiple genes, likely interacting, and probably different sets of genes in different people, that contribute to TS,” he said.

Provided by ArmMed Media
Revision date: July 4, 2011
Last revised: by Janet A. Staessen, MD, PhD