ABSTRACT
The diagnostic definition of posttraumatic stress disorder (PTSD) postulates its onset in response to external terrifying events. While an exposure to traumatic conditions is likely to cause serious distress in almost any individual, only a proportion of them develop clinical features of PTSD (1). Epidemiological studies estimate that 40% to 90% of the general population may experience traumatic events during their life, but that only 15% to 24% develop PTSD (2-4). Thus, the exposure to a traumatic event is necessary, but not sufficient factor in the etiology of PTSD. Among various factors underlying the individual vulnerability to PTSD, the genetics may have an important role in the onset and course of this disease. The genetics of PTSD are often overlooked, with only few recent reviews drawing attention to this intriguing topic (5-8). Relatively scarce genetic research is in contrast with growing need to understand the predisposition and risks for PTSD. This chapter summarizes available studies and findings, which contribute to a better recognition of the genetic mechanisms of PTSD, keeping in mind limitations and problems accompanying this type of research. In addition, we discuss novel genetic approaches and directions to stimulate further investigations in this area.
