What is the evidence that autism is genetic?

Yeah, I just want to follow up with a question because I'm hearing from an increasing number of families of adults that they got a chromosomal microarray 20 years ago, 15 years ago, and should they get a whole genome sequence, number one, or then they were retested with a whole genome sequence and the the test found something.

So can you explain to people who may not, and I've tried to explain, can you explain why you would find nothing 20 years ago, but then you would find something on a different platform today?

Correct.

So if you use the microarray, it scans one million features across the genome, of which there's 3.2 billion features.

And then we find, as I said earlier, 7% of people carry a copy number variation.

This is a gain or a loss of a segment of DNA that's typically tens of thousands of chemical bases long.

If you think about using different resolutions of a telescope looking out into space, certain lenses will allow you to see further or deeper into space and others not.

And then when whole genome sequencing came about, and there's different versions of whole genome sequencing, but now we actually get all 3.2 billion chemical letters of information.

So it's a much higher resolution, so you have the ability to find more of these genetic changes.

And if you do that, it goes up to this 20% number that I talked about.

And that's the standard test that's being done now.

So in Toronto, for example, in the province of Ontario, our Ministry of Health pays for the genetic testing, whole genome sequence-based, for people who have an autism diagnosis.

And that's starting to spread across North America.

I would say that your audience has probably also heard about the next generation of long-read genome sequencing.

I mean, a big question in the field is, you know, if we didn't find anything on microarray or for whole genome, the typical standard whole genome sequencing, if you do a long-read what's the likelihood we'll find something? We think that'll add a couple percent more.

The difference is you can actually detect so-called methylation changes along the DNA sequence.

So I think that may inch it up to maybe 25% yield.

Those experiments are still being done by our group and many others.

There's other technologies that can be used too that will be tested over time.

But that's kind of the state of the art where we're

So I've been telling people, and you should feel free to disagree with me, that if they got a chromosomal microarray more than 15 years ago and they're still concerned or have questions about a genetic finding, they should go ahead and maybe get retested.

Either talk to the primary physician that diagnosed them or I will share in the podcast notes a list of resources, at least the United States and Canada.

Some in Canada, you can help me add to them.

of places where if the insurance will not cover it, there's a number of research projects that are looking to use whole genome sequencing specifically to get a better handle on it.

So, you know, first go through your doctor, but I can't account for everybody's insurance, and I certainly don't think that anyone should have to pay out of pocket for it.