What Role Do Genetics Play in Autism?

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[MUSIC] It's a little more complicated that just running in families. So if fairly strong finding now, is that in many cases, genetic mutations occur spontaneously, so that they're not mutations that mum had or the dad had, but they occur spontaneously in the sperm or the egg or during early development.

And these demur, that is for the first time, these new mutations are clearly a major part of autism. So in that sense it's not something that runs in the family, it's a spontaneous new mutation that's there. It's known that older dads are at greater risk of having an autistic child, because mutation rates continue to increase and that would be in sperm, there's also risk factors that involve mom's health in probably first or second trimester and so these together, probably conspire to produce what we think of as autism.

All of us have mutations so all of us carry mutations in our genome, scores of mutations, mutations that weren't there in our mom's or dad's and they arose in, within our life with our own individual life and these mutations are mostly occurring in locations that don't impede or impair in any major way.

So what's strange in autism is that the rates of mutation, that is, the number of genes that one can find that are mutated in an autistic child versus me or you, are about the same. so it's probably not the number of mutations or the number these new demur mutations that occur spontaneously admitting that my mom and dad didn't have or spontaneously on or not just an autistic child that their mom and dad didn't have.

It's more of which genes are affected potentially the bad luck of the mutation occurring in critical gene systems, gene systems that regulate the number of brain cells, the number of connections that are made and the way those connections operate. [MUSIC].