Research that’s changing lives
DNA analysis, advanced MRIS offer insights into the brain and less invasive treatments
Increasingly powerful tools for detecting and treating mental illness are significantly improving research and patient care at the Centre for Addition and Mental Health.
One of the most useful pieces of technology at CAMH determines how patients will react to psychiatric drugs. The DNA variant analysis machine can examine a patient’s saliva sample for genetic differences that might make them susceptible to side effects.
This work used to be performed by two machines that processed one sample a day at a cost of $1,000 each. It also took a week to churn out results. The new all-in-one model, introduced a year ago, can analyze 10 samples a day at a tenth of the cost and provide answers the next day.
“The process has become more efficient and economical, which allows us to do research at a faster pace,” says Dr. James L. Kennedy, director of the Neuroscience Research Department at CAMH, the first psychiatric facility in the world to use the machine.
Kennedy’s work focuses on pharmacogenetics, an area of personalized medicine that investigates how genetics influence responses to psychiatric medications. His research has identified a new genetic risk factor that explains why some schizophrenic patients gain excessive weight on certain drugs. Prescreening for genetic risk factors reduces the trial and error in finding the right drugs for patients, Kennedy says.
This summer, CAMH will be the first psychiatric facility ever to receive a DNA sequencing machine, which can examine single DNA molecules in the genes that react with psychiatric drugs. This testing will reveal how people of different ancestries respond to different medications, making it possible to create individualized drug regimes.
As well, Kennedy is working to make personalized medicine mainstream through “lab-on-a-chip” biotechnology that would allow patients to easily share their genetic risk data with health-care providers.
“They could store their genetic information on their smartphone or on a chip and provide it to their doctor, or have it on hand at an ER if they ever need emergency medicine,” Kennedy says.
A different kind of technology at CAMH is shedding new light on the causes and possible cures for Alzheimer’s disease. The advanced magnetic resonance imaging (MRI) machines at the new Research Imaging Centre have helped Dr. Aristotle Voineskos detect a critical gene variation that’s involved in both promoting learning and memory and in predisposing the brain to the disease.
In a study of 69 healthy participants, Voineskos used diffusion MRI, which shows the tiniest details of biological materials, to study the gene, called brain-derived neurotrophic factor, or BDNF. In brains with a BDNF variant, he could detect subtle but important differences in memory-related architecture, including in cortex thickness and white-matter connections.
At the same time, this gene produces a vital protein that enhances the brain’s plasticity, or ability to learn new things. “With this gene variation, there is a link between the risk it poses and the treatment it could offer. If we can figure out how to finetune BDNF expression in the brain, it may help people at risk of Alzheimer’s,” Voineskos says. The brain changes caused by this variant take years to occur, making it possible to determine if someone has a predisposition before full-blown Alzheimer’s hits. This long gap between initial signs and full-blown symptoms provides a window of opportunity for Voineskos to research how to use this memory-aiding gene to delay and, ideally, treat Alzheimer’s. “With the imaging machines we have, we can go beyond the highways of the brain and permeate the roads or streets to get a more refined understanding of how the brain is connected,” Voineskos says. Technology at CAMH is not only helping researchers better understand mental illness, but offering less invasive treatment options. A perfect example is repetitive Transcranial Magnetic Stimulation, or rTMS, an intervention CAMH doctors have been using since the early 2000s to treat depression and schizo- phrenia. The approach involves uses a magnetic field to deliver a weak electric current to targeted sites in the brain.
“It activates brain cells and can help with improving plasticity. It achieves really good results with many patients,” says Dr. Jeff Daskalakis, director of the Brain Stimulation Research and Treatment Program at CAMH, which was the first psychiatric centre in Canada to use rTMS for mental illness.
Previously, the only type of brain-stimulation treatment for mental illness was electroconvulsive therapy (ECT), which involves electrically inducing seizures to promote healing. While it can work —Daskalakis says there is about a 30-per-cent higher response rate to ECT over rTMS—it produces nasty side effects such as migraines, nausea, memory loss and seizures. As well, patients must be anaesthetized during a procedure.
By contrast, rTMS has few to no side effects and patients can stay awake throughout the process.
“Even though ECT is more effective, many patients don’t want the endless courses of seizures in their brain,” Daskalakis says. “rTMS gives them another option.”