Drs. Cathy Barr and Paul Sandor at the Krembil Research Institute contributed to a landmark study on the genetic underpinnings of brain disorders. The study was published in Science and involved over 400 researchers from around the world.
As part of the study, the international team led by researchers at Harvard University examined the genetic information of more than 200,000 patients, each affected by one of 25 common brain disorders.
Drs. Barr and Sandor served as experts on the genetics of Tourette syndrome, a neurodevelopmental disorder that causes a person to make involuntary movements and sounds. Drs. Barr and Sandor have been collecting genetic samples from affected patients for decades, looking for genes that created risk for the disorder.
"In Tourette syndrome research, we thought the disorder was passed on through simple heredity—where one gene is passed on—because we had seen multiple generations of people in one family affected with Tourette syndrome," says Dr. Sandor.
"But it was actually difficult to pin down a single gene," he adds. "Now, thanks to the pooling of these samples for this study, we know that Tourette syndrome is actually caused by the interaction of a multiplicity of genes—it could be a dozen or more—and that dose of unfavourable genes also determines whether a patient has a mild, moderate or severe case of Tourette syndrome."
The landmark study also revealed that psychiatric disorders, such as bipolar disorder and major depressive disorder, appear to be more genetically similar than originally thought. In contrast, neurological disorders such as Alzheimer disease tend to be more genetically distinct.
A better understanding of these genetic relationships will enable researchers to identify the mechanisms underlying these illnesses and lead to better treatment and more effective interventions. "It's an exciting time for this research," says Dr. Barr. "With better technology and bigger samples, I really feel my earlier work will pay off and that this will translate into improved treatments for patients in my lifetime."
To read more, see the full story at UHN.ca.
Brainstorm Consortium et al. Analysis of shared heritability in common disorders of the brain. Science. 2018 Jun 22. doi: 10.1126/science.aap8757.