Study Identifies Genes Linked to Post Traumatic Stress Disorder (PTSD)

By: Sierra Shumate

In a recent study at Emory University, neuroscientist Raul Andero Gali, talks about the prevention of PTSD-like symptoms through treatment. The study, which researched drugs that can prevent reactions to trauma, shows that the prospects for developing an actual treatment are relatively high, according to Sheena Josselyn, of the University of Toronto.

Post Traumatic Stress Disorder consists of feelings of worry or fear long after danger is avoided--it can often occur after a traumatic, short lived or chronic situation. The study on the disorder was performed by a team or researchers who set out to find genes that would explain why some victims are more vulnerable to PTSD than others.

Scientists used mice and taped them to wooden boards for two hours each--a trap hat can cause PTSD like symptoms such as memory problems and anxiety. One group of mice was the control group, which was not exposed to any type of stress. Both groups of mice were then killed and amygdala tissue was removed, screened, and analyzed in order to see how the genes were expressed. 

One difference was found--OPRL21, a gene which instructed the brain how to make a receptor for the chemical nociceptin. 

More mice were traumatized in order to see if activating the receptor with a drug would have any effect on PTSD like symptoms. The mice were classically conditioned to hear a tone and then expect a mild electric shock immediately after. Some mice were injected with the test drug. 

The next day, researchers replayed the tone, but did not shock the mice--the mice who had received the drug learned very quickly not to fear the tone any more, while those who did not, showed more PTSD like symptoms and were still very traumatized. 

In the last steps of the study, researchers examined the OPRL1 gene in people with PTSD currently. Those who had a specific version of the gene had worse PTSD symptoms, and it was relatively common across the population.

Two experts on trauma-related mental health disorders say that this research may later be used to predict who is at greatest risk for PTSD, which can help to provide prevention treatment in the future.

Source: Los Angeles Times, Mental Health