A study of college students' reactions to the shootings at Northern Illinois University gives fresh insight into how genes may influence the psychological impact of traumatic events.
Researchers have found that symptoms similar to post-traumatic stress disorder were more common in DeKalb campus students who had certain variations in a gene that regulates levels of serotonin.
Researchers say the results could someday lead to new treatments for PTSD, and also could help predict who will develop the condition.
The research was unique because it involved 204 undergraduate women who by coincidence were taking part in a campus study that measured stress before the 2008 shootings — so before-and-after information was available.
Five students were killed and more than a dozen wounded when a gunman opened fire in a lecture hall.