University of Michigan study sheds light on post-traumatic stress disorder

U of M researchers recently published a study examining the genetic fingerprint of DNA from 100 Detroit residents, including 23 individuals suffering from post-traumatic stress  disorder.  In total, they examined more than 14,000 genes.  Among their findings was a propensity for certain immune system-controlling genes to become over-active in persons suffering from PTSD.  Their interpretation?  While it has long been believed that diseases and psychiatric conditions represent an "interplay between social and biological factors," these findings "support the idea that exposure to a traumatic event can trigger genetic changes that alter the body's immune system."  The result is severe and dysfunctional anxiety. 

Previous studies had suggested a link between "close calls" with death and a longer-lasting injury to the immune system.  This study corroborates that link by identifying "a specific biochemical reaction [a process called DNA methylation] that may be involved."  The theory is that methyl groups are added to the molecular letters that spell out the genetic code, according to the University's magazine, altering genetic activity.  Individuals suffering from PTSD had lower levels of methylation in the identified immune-system-related genes, suggesting that they were hyperactive when compared with immune system genes in other, healthy individuals.