Study of US military veterans finds overlap with release of stress hormone.

A study of more than 165,000 US military veterans has found eight gene regions linked to post traumatic stress disorder (PTSD), including one involved in the release of the stress hormone cortisol.

The researchers, led by Joel Gelernter of the Yale University School of Medicine in New Haven, US, analysed data from the Million Veterans Program, a US government initiative that aims to link the genes of a million returned service personnel with data on their military service, lifestyle and health.

PTSD is characterised by recurrent bouts of intense fear in the setting of a prior traumatic event, such as a physical or sexual assault, car crash or the experience of war.

The lifetime prevalence of PTSD in US adults is just under 7%. In veterans, however, lifetime prevalence rises to a disturbing 31% for males and 27% for females.

The team homed in on three classic symptoms of PTSD: reliving the event through intrusive memories or nightmares, often with sweating, palpitations and a sense of panic; being “hyperaroused” and on constant alert for danger, which disturbs sleep and concentration; and avoidance of people, places and even thoughts that might trigger memory of the event.

Eight genetic locations had links to those symptoms and, crucially, two of those coded for proteins involved in the release of cortisol. Cortisol is a hormone that goes up in response to stress and can strengthen memory of traumatic events.

Read the full article in Cosmos magazine here