New Gene Found for Cause of PTSD
A recent study by researchers at Emory University in Atlanta, GA and the University of Vermont has found that a gene called PACAP (pituritary adenylate cyclase-activating polypeptide) is controlled by estrogen and may explain why women have higher rates of Posttraumatic Stress Disorder (PTSD) than men.
In the study, researchers took saliva and blood samples from 1,200 inner-city, lower-income, men and women who had been exposed to trauma such as gang or drug violence, rape or shootings. In the blood samples, they found that women with higher levels of PACAP were much more likely than women with low levels of PACAP to have PTSD, but they didn't find any correlation like this in men. They discovered this was because the PACAP gene was located in the middle of a section of DNA affected by estrogen.
Because of this discovery, they did another test and found that women with stronger reactions to a sudden noise in the dark or a blast of air had a higher chance of carrying a PACAP receptor. They also tested mice conditioned to fear and found more PACAP receptors in the brains of the mice after they had been exposed to fear.
This discovery will be a great help to the mental health community because it shows that even though PTSD is considered a mental issue, it also has an underlying biological cause. Dr. Ned Kalin, Hedberg Professor and Chair of Psychiatry at the University of Wisconsin, said "It's potentially a new lead from the standpoint of understanding the molecular underpinnings of stress-related psychopathy". However, he also warns that this discovery shouldn't be looked at as the final discovery in this area of biology surrounding PTSD. "While this looks like an important lead", he said, "it shouldn't be misconstrued as the only thing, as a silver bullet".