Why do some people develop posttraumatic stress disorder (PTSD) when others—exposed to the same trauma—do not? Studies show that genetic factors interact with trauma to determine who will develop PTSD, but the mechanism for this heritability has been unknown.
Researchers at Emory University and Northern Illinois University had a unique opportunity to evaluate female college students who had been interviewed prior to, and shortly after, a mass shooting on the Northern Illinois University campus in February 2008. They used prospective psychological data, combined with salivary samples of students' DNA, to examine the link between polymorphisms within the serotonin transporter gene promoter region and PTSD/acute stress disorder symptoms that developed in the aftermath of exposure to the shooting.
Their data suggest that the serotonin transporter may mediate responses to severe trauma. “When examined in a relatively homogenous sample with shared trauma and known prior levels of child and adult trauma, the 5-HTTLPR multimarker genotype may serve as useful predictor of risk for PTSD-related symptoms in the weeks and months following the trauma,” they wrote September 5 in the online Archives of General Psychiatry.
For more about the Northern Illinois University campus shooting and the emergency response of the Illinois Division of Mental Health, see Psychiatric News at http://pn.psychiatryonline.org/content/43/6/2.full. Valuable information this topic is also presented in Clinical Manual for Management of PTSD, new this year from American Psychiatric Publishing, at www.appi.org/SearchCenter/Pages/SearchDetail.aspx?ItemId=62359.
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