Tandem DNA repeats are single repetitive sequences that – when expanded (a.k.a., tandem repeat expansions) – can cause genes to become dysregulated.

First discovered in the early 90s, these variants are now known to cause more than 50 diseases and disorders.

Dr. Ryan Yuen’s research has contributed significantly to this advance in knowledge. Dr. Yuen discovered and patented a method to detect tandem repeat expansions in complex brain disorders. He and his research team used this method to determine that tandem repeat expansions contribute to at least 3% of autism cases.

They’ve since discovered that tandem repeat expansions are also involved in schizophrenia and are currently exploring the role of expansions in other disorders like epilepsy and even brain cancer.

His work has been cited hundreds of times by other researchers seeking to improve our understanding of the genetic basis for myriad brain diseases and disorders, most recently Alzheimer’s and Parkinson’s diseases.

“Our bodies have a mechanism for changing the size of these tandem repeats and if we can identify that mechanism, we can use it to try to cure individuals. In the case of autism, we’re talking about 3% of cases where we may reverse the course of the disorder. I think that’s really a breakthrough.”

Dr. Ryan Yuen, Azrieli Future Leader in Canadian Brain Research

What’s the impact?

Dr. Yuen’s discovery adds a valuable, patented method to the genomics toolbox.

It also improves diagnosis; although genetics is known to play an important role in the development of autism, right now only 10-20% of autism cases are understood at the genetic level. A 3% boost in our understanding will eventually help more families obtain a clear diagnosis.

Dr. Yuen’s research also opens opens the door to treatment possibilities. Research by a colleague on Huntington’s Disease showed that it’s possible to shrink the size of the tandem repeat expansions in a targeted way, offering hope for delaying onset and slowing progression of diseases caused by this variant.

Dr Yuen and his team hosted a lab visit for racialized and underserved students, who are interested in science. The lab visit was part of MINA project (www.theminaproject.ca)

More on Dr. Ryan Yuen’s Research