DURHAM, N.C. Scientists at Duke University Medical Center have identified gene mutations that cause trichotillomania, a psychiatric disorder that triggers people to compulsively pull their hair.
The disorder affects between 3 percent and 5 percent of the population and is considered an impulse control disorder. Patients with trichotillomania have noticeable hair loss or patches of baldness, but they often mask their habit. As a result, the disorder often goes undiagnosed and untreated, said researchers.
The relatively unknown disorder is often accompanied by other psychiatric conditions, such as anxiety, depression, obsessive compulsive disorder or Tourette syndrome, which are better known than the hair-pulling behavior.
The Duke team found two mutations in a gene called SLITKR1 that were implicated in trichotillomania patients. The mutations account for only a small percentage of trichotillomania cases, said the scientists.
However, their findings are significant because they validate a biological basis for mental illnesses. Such illnesses have long been blamed on a person's upbringing or life experiences, said lead study investigator Stephan Zchner, M.D., assistant professor of psychiatry and researcher at the Duke Center for Human Genetics.
"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," Zchner said.
Currently, there is no specific treatment for trichotillomania, although it is sometimes successfully managed with drugs used for depression and anxiety disorders.
Results of this study will appear in the October 2006 issue of the journal Molecular Psychiatry. The research was self-funded through Duke University.