Oct 17 2005
Tourette syndrome is a distressing condition which affects one in every 100 people.
It often runs in families and is usually more severe in boys than girls.
The symptoms vary in severity from mild to severe and include tics, and involuntary movements, which can also be vocal and manifest as swearing.
They are often associated with psychological symptoms such as obsessive-compulsive or attention deficit and hyperactivity behaviours, ritualistic behaviour, sleep disorders, or learning disabilities.
Many experts acknowledge that there is a strong family pattern suggesting the condition is at least partly inherited.
However, although the child of a person with the inherited form of the condition stands a 50% chance of inheriting the culprit gene or genes, this does not necessarily mean that they will develop symptoms.
It seems that boys who have the DNA responsible for Tourette syndrome are more likely to develop symptoms than girls.
The condition often appears out of the blue, when it is known as sporadic Tourette syndrome.
It is generally thought by experts in the field to be a complicated genetic condition in many cases, probably involving several different genes.
Now scientists at Yale University in the U.S. have discovered a gene that appears to contribute to some cases of Tourette syndrome.
The gene apparently sits on chromosome 13 and was found in a young child with the syndrome.
When the Yale team checked another 174 unrelated people with Tourette to see if they too carried this DNA, two had exactly the same SLITRK1 gene.
The team says however that their discovery will only help explain a minority of the one in 100 people who have Tourette.
But according to Dr Matthew State, lead author of the study, the finding could provide an important clue in understanding Tourette on a molecular and cellular level.
He says confirmation of the syndrome, even in a small number of additional Tourette syndrome patients, will pave the way for a deeper understanding of the disease process.