Identifying Genetics that Support Resilience or Vulnerability to PTSD May Advance Treatments
Identifying Genetics that Support Resilience or Vulnerability to PTSD May Advance Treatments
A collaborative study by researchers at Columbia University's Mailman School of Public Health and the University of Michigan has identified a link between a gene known as ADRB2 and childhood adversity in leading to the development of post-traumatic stress disorder (PTSD). Since currently there is only a presumption that trauma exposure is the key feature in the development of PTSD, this research team set out to examine additional potential causes in order to develop new strategies to treat and prevent the development of this disorder, and other stress-related mental illnesses, in the future.
The researchers, including former NARSAD Grantees Israel Liberzon, M.D., of the University of Michigan, and Kerry J. Ressler, M.D., Ph.D., of Emory University, analyzed results from 810 Ohio National Guard soldiers who took part in the Ohio National Guard Study of Risk and Resilience and had reported having experienced a potentially traumatic event in their lives. They were asked about their childhood exposure to experiences of physical, sexual, or emotional abuse, or witnessing of violence between parents, as well as adult trauma. The participants were then evaluated for PTSD symptoms. A sample of non-service subjects enrolled in the Grady Trauma Project in Atlanta where Dr. Ressler works was also evaluated for childhood adversity, adult trauma and PTSD symptoms in a similar fashion.
The research team reports that two or more experiences of childhood trauma, such as abuse, linked with specific variants within the ADRB2 gene were associated with risk for adult PTSD symptoms. The individuals with a specific variant, or single nucleotide polymorphism (SNP), rs2400707, containing the ‘A’ allele were found to be resilient to developing PTSD despite exposure to childhood trauma, while the individuals with the ‘G’ allele version of this SNP and exposure to childhood trauma were found to be vulnerable to developing the illness. The researchers note that no differences were found when there were less than two types of childhood adversity, suggesting that having two or more types of childhood adversity may represent a different childhood experience during critical developmental periods.
The findings are significant for the study of the biology underlying the development of PTSD, and for the treatment and prevention of stress-related illnesses. The ADRB2 gene encodes the beta-adrenergic receptor, which responds to adrenaline, and has long been known to be integral to the “fight-or-flight” response. Despite the wealth of prior data implicating the adrenergic system, until now, there had been no genetic evidence of the connection with the ADRB2 gene and the development of PTSD.