Genetics of Post-Traumatic Stress Disorder: Review and Recommendations for Genome-Wide Association Studies
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Post-traumatic stress disorder (PTSD) is a prevalent, disabling anxiety disorder that constitutes a major health care burden. Despite evidence supporting a genetic predisposition to PTSD, the precise genetic loci remain unclear. Herein we review the current state and limitations of genetic research on PTSD. Although recent years have seen an exponential increase in the number of studies examining the influence of candidate genes on PTSD diagnosis and symptomatology, most studies have been characterized by relatively low rates of PTSD, with apparent inconsistencies in gene associations linked to marked differences in methodology. We further discuss how current advances in the genetics field can be applied to studies of PTSD, emphasizing the need to adapt a genome-wide approach that facilitates discovery rather than hypothesis testing. Genome-wide association studies offer the best opportunity to identify novel “true” risk variants for the disorder that in turn has the potential to inform our understanding of PTSD etiology.
KeywordsPost-traumatic stress disorder Trauma Genetics Genome-wide association Gene–environment interaction
Dr. Cornelis is a recipient of a Canadian Institutes of Health Research Fellowship.
Dr. Nugent is supported by National Institute of Mental Health grant K01 MH087240.
Dr. Amstadter is supported by National Institutes of Health grants K12HD055885 and KL2RR029880.
Dr. Koenen is supported by National Institutes of Health grants K08MH070627-06 and R01MH078928-03 and a Junior Faculty Sabbatical from the Harvard University School of Public Health.
No potential conflicts of interest relevant to this article were reported.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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