TORONTO – Researchers said they have identified the first gene involved in adolescent brain development that may play a role in mental health vulnerability.
According to Quebec’s Douglas Institute Research Centre, scientists have isolated a gene, DCC, which is responsible for dopamine connectivity in the medial prefrontal cortex during adolescence.
By working with mice, researchers found that dysfunction of this gene during adolescence had behavioural consequences which were carried into adulthood.
Researchers claim the finding provides the first clues toward a fuller understanding of how genetics can affect this area of brain development.
“Certain psychiatric disorders can be related to alterations in the function of the prefrontal cortex and to changes in the activity of the brain chemical dopamine,” said Cecilia Flores, senior author on the study and professor at McGill’s Department of Psychiatry.
“Prefrontal cortex wiring continues to develop into early adulthood, although the mechanisms were, until now, entirely unknown.”
The prefrontal cortex is associated with judgment, decision making, and mental flexibility — or with the ability to change plans when faced with an obstacle.
“Its functioning is important for learning, motivation, and cognitive processes,” she said. “Given its prolonged development into adulthood, this region is particularly susceptible to being shaped by life experiences in adolescence, such as stress and drugs or abuse. Such alterations in prefrontal cortex development can have long term consequences later on in life.”
While the study addressed brain development in the adolescent brain, Gordon Floyd, CEO and president of Children’s Mental Health Ontario, says mental health problems can appear and be diagnosed as early as about age two.
“Almost exactly half the children seen for mental health problems in Ontario’s system of community agencies are age 12 or less,” said Floyd.
According to the Mental Health Commission of Canada, an estimated 1.2 million Canadian children and youth are affected by mental illness—yet less than 20 per cent will receive appropriate treatment and only one in five children are receiving treatment for their disorders.
Experts and doctors say it is vital to treat teens or children with mental health symptoms as soon as the issue manifests itself because it leads to greater potential for a successful outcome and for a healthy adulthood.
Early intervention works with mental health just as it does with physical health, says Floyd.
“Treat a cold before it becomes pneumonia. Treat emerging behavior or emotional problems before they become more complex and deep-seated. It’s cheaper and more effective to nip problems in the bud – and early intervention also enables a childhood that’s characterized by happiness rather than distress.”
It is estimated that 70 per cent of childhood mental health issues can be solved with early intervention and therapy.
Floyd says the most common mental health problem among younger children is anxiety which, if left untreated, can evolve into other mood-related problems such as depression.
“Children who are unusually withdrawn or constantly distressed are often seen as requiring discipline, which is likely to increase their anxiety,” he said. “Instead, they need an opportunity to overcome their fears—such as abandonment or ‘separation’—and develop greater confidence and resilience when faced with perceived threats or setbacks.”
According to researchers, even subtle variations in DCC during adolescence produced significant alterations in prefrontal cortex function later on in life.
In order to determine whether the findings would translate to human subjects, researchers said they examined DCC expression in postmortem brains of people who had committed suicide.
“Remarkably, these brains showed higher levels of DCC expression, some 48 per cent higher when compared to control [healthy] subjects,” said the findings.
Researchers said that “by identifying the first molecule involved in how the prefrontal dopamine system matures, we now have a target for further investigation for developing pharmacological and other types of therapies.”
“We know that the DCC gene can be altered by experiences during adolescence,” said Flores. “This already gives us hope, because therapy, including social support, is itself a type of experience which might modify the function of the DCC gene during this critical time and perhaps reduce vulnerability to an illness.”
Floyd says it is important to remember that mental health problems arise from multiple causes, not only genetic, but also from social and environmental factors such as parental mental illness, extreme deprivation, abuse, and so on.
“It’s [therefore] important to base assessments and decisions about treatment on all those factors, not only on a genetic marker,” he said. “Genetic or biological causes are often addressed with pharmaceutical remedies, but non-drug therapies are usually effective for children and safer for young brains and bodies that are still developing, so extreme caution is needed.”
Floyd says that, in recent years, we have seen many examples of increasing empathy among high school students, for instance, usually because they have become aware of the struggles of their friends and peers.
“Confronting difficult problems quickly and openly always reduces the feelings of hopelessness and fear that contribute to stigma,” he said. “Stigma is reduced first by increasing knowledge and awareness, which happens most effectively when people learn to recognize their own mental health needs and the needs of those close to them,” he said.
© Shaw Media, 2013