Post Traumatic Stress Disorder (PTSD) affects roughly 20% of all veterans from the Afghanistan and Iraq wars. The disorder’s unfortunate prominence among those who’ve served prompted Lisa James, Ph.D., and Apostolos Georgopoulos, M.D., Ph.D., to investigate a genetic predisposition for PTSD. James and Georgopoulos are researchers at the Brain Sciences Center, an interdisciplinary center between the University of Minnesota Medical School’s Department of Neuroscience and the Veterans Affairs Health Care System.
The study assessed self-reported symptoms of PTSD and blood samples from 343 U.S. veterans. Upon running genetic tests, James and Georgopoulos found a specific protein present in the brain partially determined whether an individual was more resilient or more susceptible to being diagnosed with PTSD.
That protein is called apolipoprotein E.
Georgopoulos explained, “Apolipoprotein E moves lipids across cells in the brain. It cleans up the damage and debris, so to speak.”
Within apolipoprotein E, there are three major forms: E2, E3 and E4. The E2 allele appears to make individuals more resilient to trauma while the E4 allele increases the likelihood an individual will experience PTSD following a trauma.
“Prior to this study, we didn’t know a lot about genetic contributions to resilience,” said James. “These findings identify a specific gene that explain why some develop PTSD and others don’t.”
The study was published in Experimental Brain Research.
Looking forward, there is a national push to research ways the E4 form of this protein can be structurally modified to look and act like the more desirable E2. This modification would not only make individuals more resistant to PTSD, but potentially also to Alzheimer’s disease.
James hopes to continue examining other genes contributing to resilience. She is currently following a group of women between ages of 25 and 102 to better understand why some experience cognitive decline during aging and others do not.
This effort has been tremendously boosted by a recent $1 million gift to establish the Kunin Professorship in Women’s Healthy Brain Aging under the Department of Neuroscience, a professorship which James holds.
While these studies are in the early stages, the team is hopeful they will lead to breakthroughs in understanding the mechanisms in the brain that promote resilience.
“Resilience goes beyond PTSD. It includes Alzheimer’s, aging, and general cognitive function,” James said. “We’re interested in applying these findings toward identifying similar proteins or mechanisms related to many types of brain resilience or decline.”