One of the key roadblocks to treating neurodevelopmental disorders (NDDs) such as autism, schizophrenia or Down syndrome, is understanding the root causes of the conditions.
Dr. Karun Singh is on a mission to overcome these hurdles by leveraging the power of stem cells and gene editing technology, with the goal of developing effective treatments – or even cures – for NDDs. It's a daunting task, but one the neuroscientist relishes, especially because he has the opportunity to bring hope to families of children with NDDs.
"I interact with families all the time, and the thing I tell them is that they're taking part in the latest and most emerging research," says Dr. Singh, a newly recruited Senior Scientist at the Donald K. Johnson Eye Institute at UHN. "When we can use a stem cell-based approach, it really is a more accurate way to study their disorder."
Simply put, NDDs impair development in the brain, resulting in everything from learning disabilities to visual impairment. Scientists have struggled to study these disorders because they can't access live patient brain tissue, limiting their research capabilities.
Dr. Singh's groundbreaking work focuses on understanding how genes and genetic mutations influence neurological development. By lab-engineering brain cells from patient stem cells using sophisticated gene editing tools, he's able to study neurological conditions in a more comprehensive way.
He and his team can take a blood sample from an individual with a specific brain disorder, then mimic what's happening in the person's brain in a controlled laboratory setting, without invasive testing.
"Many of the brain development disorders that we study are caused by genetic mutations," explains Dr. Singh, who joined UHN in June 2020, after earning accolades for his work at the Stem Cell and Cancer Research Institute at McMaster University in Hamilton. "We try to model that [genetic defect] in the lab by creating stem cells from the person's blood and then recreating their brain tissue in a dish."
Dr. Singh is using the same approach to model eye tissue in the lab, gaining insight into the visual impairment caused by NDDs and the development of vision disorders like macular degeneration.
He explains that once they understand the molecular dysfunction happening in the brain, they can find an already–approved drug which targets that particular molecular dysfunction and might correct the deficiency.
"If it's a different drug that's normally used to treat cancer, for example, we can repurpose it for this neurological brain development disorder caused by a genetic defect," says Dr. Singh.
"In order to know which drug to choose, you have to know, at the molecular level, what's wrong."
