Autistic Mice Help Examine Genetic Links to Autism
Gone are the days where we blame autism on “refrigerator moms” who did not “hold their children enough” in their younger years. Yes, that used to be an accusation in the 1950s and 1960s. In modern times, we understand that autism is nearly always based on genetic changes in the person’s DNA. Right now, up to 80% of autism cases have a known genetic DNA link, and I have a feeling the other 20% are situations we just haven’t identified yet.
That’s where autistic mice come in.
A young man, Jake Litvag, was fortunate enough to have parents who were both wholly committed to the science and also people with a fair amount of money. First, they were able to get Jake’s DNA sequenced to determine that the particular cause of his autism was that Jake was missing a copy of the MYT1L gene. There are a variety of genetic situations which cause autism – not just one – so DNA sequencing is necessary to narrow down which gene is causing the autism.
Next, armed with this information, Jake’s parents raised $70,000 for research. With that money, scientists were able to create a CRISPR tool (gene editing) which caused that exact same lack of MYT1L in mice. The mice were then bred, so the researchers now have a whole colony of mice, all missing that MYT1L gene.
You might think a gene does only one tiny thing – like maybe make a freckle. But actually a gene can affect a whole range of things, depending on how important it is. In this particular case, researchers find MYT1L impacts obesity, mental development, and hyperactivity. That is being found to be true in both humans and in mice.
Researchers found that those mice had a number of the same traits as Jake did. They can now see in more detail exactly what happens to a body when it is missing a MYT1L gene. Yes, scientists could try scouring the world to find all humans who are missing MYT1L, but that would require a lot of genetic testing which is fairly expensive. Maybe in some future more people will know their genetic testing information and this kind of research could be easier. But for now, the only option is really to engineer mice who are missing MYT1L and to study them, to get more information on what happens to a living organism when its MYT1L is missing.
DNA changes like this happen for various reasons. It could be both parents are missing MYT1L and therefore their child is also missing MYT1L. The reports do not go into that aspect of the situation. It could also be, though, that the very normal occasional mis-translations that happen while an embryo is forming sometimes cause DNA bits to be altered or missed. No continual replication process is absolutely perfect. In every one of our bodies, there are cells which are not exactly identical to other cells. Most of the time the changes are innocuous and don’t get noticed. But sometimes, like in a case where MYT1L is somehow missed, the results are quite noticeable.
I found other studies on MYT1L involving zebrafish. They also found that a lack of MYT1L in zebrafish caused a lower level of oxytocin, which is critical to healthy brain activity. That could explain some of the other effects.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5597252/
All in all, I’m a strong proponent of genetic testing of all of us. The better we can understand our own DNA, the better we can find ways to be the very best we can be given that foundation. Also, it means we can work together on common DNA traits to help explore solutions to challenges. It might be that I have a DNA trait that others struggle with, and I have found a way to work with it. It might be I have no idea that I’ve found this solution. With DNA community forums, those sorts of situations can be found and help us all lift each other up to where we want to be.
Stock image of crowd from Pixabay / geralt