Could there be a new “cure” for Down Syndrome? The internet is buzzing today after the September 4th edition of Science Translational Medicine published a recent study about how a team of scientists from John Hopkins University used an experimental compound to reverse the Down syndrome like learning deficits in mice.
Fox news reports that they accomplished this by:
“…injecting a small molecule known as a sonic hedgehog pathway agonist into the brains of genetically engineered mice on the day of their birth. The treatment enabled the rodents’ cerebellums to grow to a normal size, allowing them to perform just as well as unmodified mice in behavioral tests…”
Roger Reeves, one of the researchers behind this study, had previously found that a characteristic of people with Down syndrome is having a cerebellum that’s approximately 60% the size of a typical person. In order for that important brain region to grow and develop, a small population of cells in the brain must quickly divide and multiply shortly after birth.
These brain cells require a specific growth factor known as sonic hedgehog pathway (not to be confused with one of the greatest video games of all time) in order to stimulate the cells to grow and divide.
The researches determined that a person with Down syndrome did not respond as well to this growth fact, and it actually stunted the development of the cerebellum (the region of the brain import to cognitive processing and emotional control.) So they thought if they could stimulate the cells at birth they could make up the deficit.
In order to test the theory, Reeves and his team used some genetically engineered mice which had extra copies of about half of the genes found in the 21st chromosome, which caused the mice to have many of the characteristics of Down syndrome such as a smaller cerebellum and learning difficulties.
The researchers injected these mice with a sonic hedgehog pathway agonist on the day of their birth. Here’s what they found:
“From that one injection, we were able to normalize the growth of the cerebellum, and they continued to have a structurally normal cerebellum when they grew up.”
In further testing the “mice with Down syndrome” preformed just as well as “typical mice” at tests that measured their spatial learning and memory capabilities.
In other words, they “cured” some of the characteristics of Down syndrome in these mice.
This treatment has yet to be proven effective in humans with Down syndrome, and future research is needed to determine exactly how and why the injection improved the mice’s cognitive abilities.
It’s also important to note that this study is aimed at new babies born with Down syndrome, unlike this study that is working on improving the life of people already living with Down syndrome (like my son.)
Studies like this bring up a lot of questions and thoughts for me; to many to go into on this blog post. However, I’d love to hear your thoughts about this study and the conversation about “curing Down syndrome” in general. Would you allow your child to take medication to help them with some of the cognitive / learning delays that is often a characteristic of people born with Down Syndrome? Why or why not?
Leave your comments / thoughts below and let me know what you think.