A gene known to play a role in protecting brain cells from the damaging effects of stress may also be involved in the development of post-traumatic stress disorder (PTSD), according to new research.
Researchers at Boston University School of Medicine and Veterans Affairs Boston Healthcare System note the results of a genome-wide association study of PTSD suggest that variations in the retinoid-related orphan receptor alpha (RORA) gene are linked to the development of PTSD.
Previous studies estimate that approximately 8 percent of the U.S. population will develop PTSD in their lifetime. That number is significantly greater among combat veterans, where as many as one out of five suffer symptoms of PTSD, researchers say.
Previous studies also have linked the RORA gene to other psychiatric conditions, including attention-deficit hyperactivity disorder, bipolar disorder, autism, and depression.
“Like PTSD, all of these conditions have been linked to alterations in brain functioning, so it is particularly interesting that one of the primary functions of RORA is to protect brain cells from the damaging effects of oxidative stress, hypoxia and inflammation,” said Mark W. Miller, Ph.D., associate professor.
Participants in the study included approximately 500 male and female veterans and their partners, all of whom had experienced trauma and approximately half of whom had PTSD. The majority of the veterans had been exposed to trauma related to their military experience while their partners had experienced trauma related to other experiences, such as sexual or physical assault, serious accidents, or the sudden death of a loved one.
Each participant was interviewed by a trained clinician and DNA was extracted from samples of their blood.
The DNA analysis, which examined approximately 1.5 million genetic markers for signs of association with PTSD, revealed a highly significant association with a variant (rs8042149) in the RORA gene.
The researchers then looked for evidence of replication using data from the Detroit Neighborhood Health Study where they also found a significant, though weaker, association between RORA and PTSD.
“These results suggest that individuals with the RORA risk variant are more likely to develop PTSD following trauma exposure and point to a new avenue for research on how the brain responds to trauma,” said Miller.