UCLA scientists have discovered two genes that may explain why some people suffer post-traumatic stress disorder while others with similar experiences do not.
The findings, reported in the Journal of Affective Disorders, could point the way to new ways to diagnose and treat the condition.
University of California-Los Angeles researchers identified the genes by examining DNA from 200 adults from 12 extended families who suffered PTSD symptoms after surviving the 1988 earthquake in Armenia.
They found that people with specific variants of two genes were more likely to develop PTSD symptoms. Called TPH1 and TPH2, these genes control the production of serotonin, a brain chemical that regulates mood, sleep and alertness -- which are disrupted in PTSD.
"People can develop post-traumatic stress disorder after surviving a life-threatening ordeal like war, rape or a natural disaster," said lead author Dr. Armen Goenjian, psychiatric specialist at the Semel Institute for Neuroscience and Human Behavior at UCLA. "If confirmed, our findings could eventually lead to new ways to screen people at risk for PTSD and target specific medicines for preventing and treating the disorder."
PTSD symptoms affect about 7 percent of Americans who have experienced child abuse, terrorist attacks, sexual or physical assault, major accidents, natural disasters or exposure to war or combat. Symptoms include flashbacks, feeling emotionally numb or hyper-alert to danger, and avoiding situations that remind one of the original trauma.