Boston researchers have identified a gene that seems to be associated with post-traumatic stress disorder.
The gene, called retinoid-related orphan receptor alpha (RORA), is also known for its role in protecting brain cells from oxidative stress and inflammation, researchers said. Their findings are published in the journal Molecular Psychiatry.
Researchers were able to identify the gene by conducting a genome-wide association study of about 500 veterans and their partners -- 295 had PTSD, while 196 did not. The veterans were more likely to have PTSD because of a military-related experience, while the non-veterans were more likely to have PTSD because of assault reasons.
The researchers conducted the genome-wide association study by taking blood samples from all the study participants in order to analyze their DNA.
The findings "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," study researcher Mark W. Miller, Ph.D., an associate professor at the Boston University School of Medicine, said in a statement.
This is not the first time a particular gene has been associated with post-traumatic stress disorder. Earlier this year, University of California, Los Angeles researchers found that two genes called TPH1 and TPH2, which are already known to be involved in the production of serotonin, are linked with a higher risk of developing PTSD.
"We suspect that the gene variants produce less serotonin, predisposing these family members to PTSD after exposure to violence or disaster," study researcher Dr. Armen Goenjian said in a statement. "Our next step will be to try and replicate the findings in a larger, more heterogeneous population."
In that study, researchers studied the genes of 200 adults who were affected by the 1988 Armenia earthquake and developed PTSD symptoms.
And in a Proceedings of the National Academy of Sciences study of genocide survivors from Rwanda, a gene associated with improved ability to remember emotional memories was also linked with an increased risk of PTSD, CNN reported.
"Some people have very, very detailed visual memories," study researcher Keith A. Young, Ph.D., of the Texas A&M Health Science Center College of Medicine, told CNN. "Perhaps there's something about that detailed kind of visual memory that makes it easier for you to have a flashback. That's one explanation."