My fascination with neuroscience began with a developmental biology class in college.
How can you start with a sperm and an egg and end up with a complete organism? That’s amazing enough, and then there’s the development of the brain, the most complex organ in the body, what really makes us human. I just thought it was such an incredible question to be asking.
I was a researcher for the UW-Madison’s Waisman Center in 2008 when science fiction became reality. Jamie Thomson, who had discovered human embryonic stem cells a decade earlier, and Shinya Yamanaka figured out how to reprogram a person’s skin or blood cells to act like stem cells.
For those of us studying brain development, this breakthrough opened unprecedented opportunities to learn more about disorders like Down Syndrome.
We know surprisingly little about how intellectual disabilities happen because brain disorders develop prenatally. Human fetal tissue is difficult to acquire, and the typical go-to source for medical researchers doesn’t work because mice don’t have the extra chromosome found in a person with Down syndrome.
With the discovery of how to induce these so-called pluripotent stem cells, researchers can now take cells from people with specific developmental brain disorders, such as Downs, coax them into becoming brain cells, and watch how they develop. It’s almost like going back in time.
The research we are doing is very basic. We are still asking fundamental questions about how mistakes in development lead to differences in the brain, and ultimately to intellectual disability.
For instance, we know that adults with Downs syndrome have fewer nerve cells. So, we are comparing human embryonic stem cells with stem cells induced from the cells of people with Down syndrome to understand why fewer nerve cells are being generated during early brain development. What goes wrong?
This work isn’t about finding a cure, as the genetic mutation that causes Down syndrome can’t be fixed. But maybe we can improve the cognitive ability of people with this disorder to improve their quality of life.
One day it may be possible, for instance, to re-purpose existing drugs that might help improve the lives of people with intellectual disabilities.
Knowing more about development could also help us develop better learning strategies. It might be just enough to make the difference between whether a person is able to live independently or with assisted support.
Down syndrome is a prevalent disability, and we all know somebody who has it.
Thanks to the individuals and families in the Downs syndrome community who have embraced the research by donating skin and blood cells for this pioneering work, we are starting to gain at least an understanding of the causes behind it. Hopefully, we can move quickly as our understanding improves.