Genetics and Genomics of Posttraumatic Stress Disorder

PTSD is a complex disorder; a range of molecular features likely contribute to individuals' increased risk for, or resilience to, developing PTSD when exposed to trauma. This chapter reviews the existing evidence for genetic and other molecular variation that has been tested for association with PTSD in humans. The authors summarize the 30 candidate gene studies of PTSD published to date, as well as the small but growing literature documenting PTSD-associated gene expression, and the emerging evidence of epigenetic variation that underlies this disorder. This review suggests that genetic and genomic variation contributes to PTSD etiology, with effects at times moderated by the environment; however, robust findings are only arrived at through careful attention to appropriate control selection. Future research in this rapidly evolving area should consider the joint action of molecular and environmental features operating at multiple levels to shape risk for PTSD.