PTSD is one of the toughest disabilities to prove to VA, we deal with veterans every day with this terrible condition. The researchers at the University of Michigan recently issued their findings, which supports a model for PTSD in which exposure to a traumatic event changes gene expression, which in turn, alters immune-system activity, leading to the disorder. So the traumatic event (stressor) causes a change in a veteran's genes and then alters a normal immune system. Maybe this type of research, from my university, will someday be used by VA to recognize this is a real disability that affects a veteran’s body at the most basic cell level. Read about the research below.