New Michigan State University research has found that refugees diagnosed with post–traumatic stress disorder regulate stress differently than those who don’t have the disorder, but may have experienced similar suffering.

“What we discovered was that a gene associated with a person’s mental health became overactive in refugees with PTSD and wasn’t able to respond the right way when working with the body’s stress defense system,” said Bengt Arnetz, a professor of family medicine who led the study.

The methyl CpG binding protein 2 gene, or MECP2, helps control the normal function of nerve cells and plays an important role in mental health and the body’s ability to handle stress.

An individual’s stress defense system, known as the hypothalamic pituitary adrenocortical axis, or HPA, is activated when he or she is exposed to mental pressure or trauma and then calms down when the event is over. In refugees with PTSD, this built–in security system doesn’t respond correctly and continues to overreact.

The findings were presented at the American Psychosomatic Society’s annual meeting on March 18.

It’s estimated that up to a quarter of the refugees entering the United States have PTSD.

“Often times, those who come to the U.S. in search of a better life have been exposed to severe stress in one way or another,” Arnetz said. “Some of this trauma can include coping with poor environmental conditions for many years and even violent situations as a result of war.”

The federally funded study looked at 66 male and female refugees from Syria who had arrived in the United States within a month’s time. Each were interviewed and given a validated medical survey to determine if they had PTSD.

The survey, known as the PTSD Checklist–Civilian included questions on socioeconomics, exposure to trauma, as well as symptoms associated with the disorder. Refugees with scores above 30 were classified as having PTSD and were compared to those with lower scores.

Researchers also took blood samples from study participants in order to analyze the MECP2 gene activity.

Arnetz said his findings provide important information that will help advance this type of research and assist individuals who are focused on aiding refugees once they arrive.

“Because refugees have typically experienced terrible environmental factors such as air pollution, as well as severe violence and trauma, it’s important to study the impact of these things on the brain and body’s physiology in order to optimize the health, well being and social integration of this population,” he said.

Researchers from Wayne State University also contributed to the study with funding from the National Institute of Mental Health and the National Institute of Environmental Health Sciences.