PTSD genes identified by UCLA study

Why do some persons succumb to post-traumatic stress disorder (PTSD) while others who suffered the same ordeal do not? A new UCLA study may shed light on the answer.

UCLA scientists have linked two genes involved in serotonin production to a higher risk of developing PTSD. Published in the April 3 online edition of the Journal of Affective Disorders, the findings suggest that susceptibility to PTSD is inherited, pointing to new ways of screening for and treating the disorder.

"People can develop post-traumatic stress disorder after surviving a life-threatening ordeal like war, rape or a natural disaster," explained lead author Dr. Armen Goenjian, a research professor of psychiatry at the Semel Institute for Neuroscience and Human Behavior at UCLA. "If confirmed, our findings could eventually lead to new ways to screen people at risk for PTSD and target specific medicines for preventing and treating the disorder."

PTSD can arise following child abuse, terrorist attacks, sexual or physical assault, major accidents, natural disasters or exposure to war or combat. Symptoms include flashbacks, feeling emotionally numb or hyper-alert to danger, and avoiding situations that remind one of the original trauma.

Goenjian and his colleagues extracted the DNA of 200 adults from several generations of 12 extended families who suffered PTSD symptoms after surviving the devastating 1988 earthquake in Armenia.

In studying the families' genes, the researchers found that persons who possessed specific variants of two genes were more likely to develop PTSD symptoms. Called TPH1 and TPH2, these genes control the production of serotonin, a brain chemical that regulates mood, sleep and alertness -- all of which are disrupted in PTSD.

"We suspect that the gene variants produce less serotonin, predisposing these family members to PTSD after exposure to violence or disaster," said Goenjian. "Our next step will be to try and replicate the findings in a larger, more heterogeneous population."

Affecting about 7 percent of Americans, PTSD has become a pressing health issue for a large percentage of war veterans returning from Iraq and Afghanistan. The UCLA team's discovery could be used to help screen persons who may be at risk for developing PTSD.

"A diagnostic tool based upon TPH1 and TPH2 could enable military leaders to identify soldiers who are at higher risk of developing PTSD, and reassign their combat duties accordingly," observed Goenjian. "Our findings may also help scientists uncover alternative treatments for the disorder, such as gene therapy or new drugs that regulate the chemicals responsible for PTSD symptoms."

According to Goenjian, pinpointing genes connected with PTSD symptoms will help neuroscientists classify the disorder based on brain biology instead of clinical observation. Psychiatrists currently rely on a trial and error approach to identify the best medication for controlling an individual patient's symptoms.

Serotonin is the target of the popular antidepressants known as SSRIs, or selective serotonin re-uptake inhibitors, which prolong the effect of serotonin in the brain by slowing its absorption by brain cells. More physicians are prescribing SSRIs to treat psychiatric disease beyond depression, including PTSD and obsessive compulsive disorder.


Also see: http://www.bbc.co.uk/news/health-17560680

PTSD passed on from one generation to the next

Writing for Indian Country Today Media Network, Beverly Cook (Wolf Clan Mohawk) discusses how acts of genocide perpetrated upon Native Americans has passed "toxic stress" down the line from one generation to the next and how the evils of the past continue to hurt the people of today:

Toxic stress experienced by children can alter their brain, their genes and organ development if they do not have the caring support of an adult. So a young girl’s childhood experiences, her health and her diet will not only effect the outcome of her future pregnancies but also can effect her future grandchildren. She is not alone in this as the genes that come from the father have also been imprinted by his childhood and his environment in his mother’s womb. Combined, the mother and father lay the groundwork for their baby to grow and still the actual outcome can change depending on the environment in the womb. Imagine no worries or concerns, having nutritious food, adequate exercise, a loving partner, happiness and peace. The baby would form itself based on that particular environment as opposed to an environment laced with anger, fear, frustration or grief.

Read more here:

The Toxic Effects of Stress on American Indians

PTSD affects childrens' DNA

Childhood trauma can lead to PTSD in adults, while also affecting them on a genetic level.

According to a study published in the journal Biological Psychiatry, adults with PTSD who had a history of childhood trauma had a significantly shorter region of DNA proteins known as the telomere -- a region of repetitive DNA sequence at the end of a chromosome which protects the chromosome from deterioration. Previous studies have linked short telomere length with accelerated aging and a greater risk of cardiovascular disease, cancer, and other degenerative conditions.

The study examined a total of 90 people -- 47 with PTSD and 43 without. The subjects with PTSD were found to have an average telomere length shorter than that of the non-PTSD subjects.

Read more here:

Risk of Accelerated Aging Seen in PTSD Patients with Childhood Trauma

Research: Stress (and its damage) Can Be Passed on Genetically

According to new research, some of the effects of PTSD could possibly be passed on to your offspring, or even make your children more likely to develop PTSD if they encounter their own traumatic events. 

A study of Holocaust survivors found that their children were more susceptible to PTSD because the bodies of both parents and children generated lower levels of cortisol, a hormone that helps shut down the stress response.

The Independent has much more on this research in a recent article:

Stressed out? It could be in your genes