GENES RESPONSIBLE FOR POST-TRAUMATIC STRESS DISORDER IDENTIFIED
Daily News & Analysis
April 3 2012
UCLA scientists may have found answer to why some persons succumb to
post-traumatic stress disorder (PTSD) while others who suffered the
same ordeal do not.
They have linked two genes involved in serotonin production to a
higher risk of developing PTSD.
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 Behaviour
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,” he suggested.
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. Our next step will be to try and replicate the findings
in a larger, more heterogeneous population,” said Goenjian. ”
Affecting about 7% 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,” noted 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,” he added.
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.
The scientists published their finding in the April 3 online edition
of the Journal of Affective Disorders.
From: A. Papazian
http://www.dnaindia.com/scitech/report_genes-responsible-for-post-traumatic-stress-disorder-identified_1671108