U.S. soldiers in Iraq in 2003
U.S. soldiers guard a burning oil well in Iraq in 2003. Navy photo via Wikimedia Commons

A study by led scientists at UC San Diego and Yale University has found a genetic factor in the post-traumatic stress disorder that has afflicted many American veterans.

The study of more than 165,000 veterans found eight distinct genetic regions with strong associations between PTSD and how the brain responds to stress.

The study, published Monday in the journal Nature Neuroscience, focused on the role of a type of brain cell — a striatal medium spinal neuron — that is prevalent in a region responsible for motivation, reward, reinforcement and aversion.

“The genes implicated in this study point to this region of the brain, and these types of neurons, as potentially involved in PTSD vulnerability,” said Murray B. Stein, a professor at the UC San Diego School of Medicine and a psychiatrist at Veterans Affairs San Diego Healthcare System.

“Because we know something about the regulation of these neurons, we can test hypotheses about drugs that might be useful for PTSD, such as drugs that influence dopamine,” he said.

Co-leader of the study was Joel Gelernter, professor of psychiatry, genetics and neuroscience at Yale School of Medicine and VA Connecticut Healthcare System.

The scientists used a new technique called a genome-wide association study that analyzed genetic data from members of the Million Veteran Program, a national voluntary research effort.

PTSD is characterized by unintentional and unwanted recall, emotions and behaviors linked to past traumatic events, such as flashbacks.

Chris Jennewein is Editor & Publisher of Times of San Diego.