THURSDAY, Aug. 3, 2006 (HealthDay News) -- A newly identified genetic factor may explain how and why obsessive-compulsive disorder (OCD) runs in families, two new studies conclude.
Close relatives of people with OCD are up to nine times more likely than other people to develop OCD.
The two studies, published in the current issue of the Archives of General Psychiatry, found an association between OCD and a glutamate transporter gene called SLC1A1. The gene encodes a protein called EAAC1 that regulates the flow of glutamate in and out of brain cells. Variations in the SLC1A1 gene may cause changes in the flow of glutamate, which may put a person at increased risk of developing OCD, the researchers suggested.
One study was conducted by researchers from the University of Michigan, the University of Illinois at Chicago, and the University of Chicago. That study included 71 OCD patients (children and adults) and their parents.
The other study, by University of Toronto researchers, included 157 OCD patients and 319 of their first-degree relatives.
"Taken together, these findings suggest that SLC1A1 is a strong candidate gene for OCD, which if confirmed could lead to improvements in understanding and treating this condition, and screening those with an elevated risk," Dr. Gregory Hanna, senior author on one of the studies and an associate professor of psychiatry at the University of Michigan Medical School, said in a prepared statement.
"It's possible that altered glutamate activity in some brain regions may contribute to the obsessions and compulsions that are the hallmark of OCD," Hanna said.
The American Medical Association has more about OCD.