Recent Genetics and Epigenetics Approaches to PTSD
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Purpose of Review
Following a life-threatening traumatic exposure, about 10% of those exposed are at considerable risk for developing posttraumatic stress disorder (PTSD), a severe and disabling syndrome characterized by uncontrollable intrusive memories, nightmares, avoidance behaviors, and hyperarousal in addition to impaired cognition and negative emotion symptoms. This review will explore recent genetic and epigenetic approaches to PTSD that explain some of the differential risk following trauma exposure.
A substantial portion of the variance explaining differential risk responses to trauma exposure may be explained by differential inherited and acquired genetic and epigenetic risk. This biological risk is complemented by alterations in the functional regulation of genes via environmentally induced epigenetic changes, including prior childhood and adult trauma exposure.
This review will cover recent findings from large-scale genome-wide association studies as well as newer epigenome-wide studies. We will also discuss future “phenome-wide” studies utilizing electronic medical records as well as targeted genetic studies focusing on mechanistic ways in which specific genetic or epigenetic alterations regulate the biological risk for PTSD.
KeywordsPTSD Genetics Epigenetics GWAS DNA methylation
The work was supported by NIH grants R01MH108665, R01MH094757, and R21MH112956 to KJR, a NARSAD Award to NPD, and the Frazier Foundation Grant for Mood and Anxiety Research to KJR.
Compliance with Ethical Standards
Conflict of Interest
Nikolaos P. Daskalakis, Chuda M. Rijal, Christopher King, and Laura M. Huckins declare no conflict of interest.
Kerry J. Ressler is on the Scientific Advisory Boards for Resilience Therapeutics, Sheppard Pratt-Lieber Research Institute, Laureate Institute for Brain Research, The Army STARRS Project, UCSD VA Center of Excellence for Stress and Mental Health—CESAMH, and the Anxiety and Depression Association of America. He provides fee-for-service consultation for Biogen and Resilience Therapeutics. He holds patents for use of D-cycloserine and psychotherapy, targeting PAC1 receptor for extinction, targeting tachykinin 2 for prevention of fear, targeting angiotensin to improve extinction of fear. Dr. Ressler is also founding member of Extinction Pharmaceuticals to develop d-Cycloserine to augment the effectiveness of psychotherapy, for which he has received no equity or income within the last 3 years. He receives or has received research funding from NIMH, HHMI, NARSAD, and the Burroughs Wellcome Foundation.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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