A new study suggests mutations in a gene called SLITKR1 may play a role in the development of trichotillomania in some families. The mental disorder causes people to compulsively pull their hair out, resulting in noticeable hair loss and bald spots.
Researcher Stephan Züchner, M.D., of the Duke Center for Human Genetics, says genetic mutations only account for a small fraction of trichotillomania cases, but the findings may help lead to a better understanding of the unusual disorder.
"Society still holds negative perceptions about psychiatric conditions such as trichotillomania. But, if we can show they have a genetic origin, we can improve diagnosis, develop new therapies, and reduce the stereotypes associated with mental illness," Züchner says in a news release.
Researchers say trichotillomania affects between 3 percent and 5 percent of the population. It's considered an impulse control disorder and can be accompanied by other mental illnesses, such as anxiety, depression, obsessive-compulsive disorder, or Tourette's syndrome.
In the study, published in Molecular Psychiatry, researchers studied 44 families in which one or more members had trichotillomania. They focused on the gene SLITRK1 because a previous study had linked it to Tourette's syndrome, a related impulse-control disorder.
The study showed two mutations in this gene were found among family members with trichotillomania, but not in unaffected family members. Researchers estimate these mutations account for about 5 percent of trichotillomania cases.
Although the SLITRK1 gene is the first to be linked to trichotillomania, researchers say many other genes likely contribute to the disorder.
"The SLITRK1 gene could be among many other genes that are likely [to] interact with each other and environmental factors to trigger trichotillomania and other psychiatric conditions," says researcher Allison Ashley-Koch, Ph.D., assistant professor of medical genetics at Duke University, in the release.
SOURCES: Zuchner, S. Molecular Psychiatry, October 2006, Vol. 11. News release, Duke University Medical Center.
By Jennifer Warner
Reviewed by Brunilda Nazario