Autism spectrum disorder is a complex neurodevelopmental condition with challenges that can vary widely in how they affect each individual.
But there’s been plenty of misinformation in the news and on social media about what causes autism.
KERA’s Sam Baker talks with Dr. Maria Chahrour, a neurogeneticist at UT Southwestern’s O’Donnell Brain Institute, about her research into the role of genetics in autism.
Dr. Chahrour: For about 35% of cases, we can attribute the cause to specific genetic variants, and these are changes in our genome or our DNA sequence that can either occur spontaneously or they can be passed down or inherited.
So far as a field, we've identified hundreds of genes that are involved. Many of them affect brain development, they affect how our neurons communicate with one another. Or they're genes that essentially regulate the expression of many other genes.
And environmental factors may play a role in some cases of autism.
Baker: Environmental factors such as what?
For example, there are some environmental factors that can affect autism risk in individuals who are already genetically susceptible, medical conditions and illnesses during pregnancy, also birth complications, and finally, parental age. So, it can either be advanced maternal or paternal age at conception.
Can you give me an idea of your work at UT Southwestern regarding genetic and environmental factors affecting autism?
We run a human genetics research study where we're looking for these genetic risk factors in individuals and families with the condition. We sequence their genomes and we look for variants or changes in the DNA sequence that could be increasing risk. This provides more rapid and more accurate diagnoses.
Eventually what this does is it leads to the development of treatments that are targeted at these genes and also targeted at the specific biological mechanisms that these genes function in. And this leads to more individualized healthcare.
We also have research that is focused not only at treating the symptoms, but also enhancing the quality of life, independence, and wellbeing for autistic people across the lifespan.
Studies linking autism to vaccines have been debunked, but those concerns still continue out there. They're still spread around. What do you suppose that is?
You know, as humans, we naturally seek answers for complex questions that don't immediately have clear answers. And autism is often diagnosed around the same age that children receive their key vaccines, which leads to this mistaken belief that vaccination causes autism, simply because one event follows another.
There's also the fact that the misinformation that gets shared on social media, it just spreads very quickly online. And that's unfortunately what happened with the initial or the original claim that ended up being fraudulent and was thoroughly discredited.
In the meantime, the latest CDC report on autism says the rate of diagnosis has increased from one in 36 children to one in 31. What's really happening here? Why the increase in diagnosed cases?
The main reasons for this rise are the broader diagnostic criteria and increased awareness. So now more children are being identified because we've essentially expanded the definitions of autism.
And also, there's greater recognition of its signs by health care providers, by educators, and by families. There's also improved access to these diagnostic services, which is closing previous gaps that we and identification efforts. And there's earlier and more frequent screening.
So, children are being evaluated and diagnosed at much younger ages, leading to higher reported prevalence.
RESOURCES:
‘Autism Epidemic Runs Rampant,’ New Data Shows 1 in 31 Children Afflicted
