This Autism Speaks fellow is exploring the genetic subtypes of autism to guide the development of personalized interventions
By Daniel Tylee, a 2015 Autism Speaks Dennis Weatherstone predoctoral fellow. Mr. Tylee is a dual MD/PhD candidate at the State University of New York Upstate Medical University, in Syracuse. As part of his fellowship project – “Advanced Autism Genetics” – he is identifying genetic subgroups of autism, determining whether these groups share biological similarities and looking for autism “resilience” genes that may confer protection against the condition. He is pursuing this work in the Psychiatric Genetic Epidemiology & Neurobiology Laboratory of Stephen Glatt.
I greatly appreciate this opportunity to share my Weatherstone fellowship project with the Autism Speaks community. I thank you for supporting my work.
My research involves tackling the challenge of biological heterogeneity in autism. With respect to autism, the word heterogeneous can have different meanings in different contexts. For example, anyone who knows more than one person with autism knows that its symptoms affect no two people in exactly the same way. Autism is indeed a spectrum when it comes to people’s intellectual and social skills.
We also know that many – but not all – people with autism have co-occurring medical conditions such as gastrointestinal issues, seizures, sleep disturbances and/or anxiety.
The challenge of autism’s complexity
As researchers, we also recognize autism’s great biological and genetic heterogeneity. We know that hundreds of different genetic changes can contribute to autism. Yet in many cases, we can’t identify any one genetic reason for a person’s autism. You may hear this referred to as “idiopathic” autism – meaning “cause unknown.” For these individuals, it’s likely that a number of weaker genetic and nongenetic risk factors interact to change early brain development.
Each year we’re learning more about the nongenetic, or “environmental,” risk factors for autism. Some of the clearest include maternal infection during pregnancy and extreme prematurity. These influences don’t cause autism in and of themselves, but they can increase risk when combined with genetic risk factors.
As you might imagine, autism’s great heterogeneity can complicate the search for autism’s causes and treatments. Typically, researchers learn about a condition by taking a large group of study participants who are affected by a condition and compare them with a large sample of unaffected individuals. We then ask the question: “What is different?”
However, if the sample of autism-affected individuals is composed of many distinct subsets of people, then similarities and difference between “affected” and “not affected” can become difficult to find.
Why I’m so hopeful
As a scientist, parent or person with autism, this situation may seem disheartening. But I want to share with you why I have great hope for this avenue of autism research.
In my research, I’m using advanced computational tools to identify subgroups of autism-affected individuals. Each group shares a common set of genetic risk factors. We hope that each of these distinct genetic “signatures” will provide unique insights into the many ways that brain development can become altered to produce autism.
Through studies like this, we hope to clarify and transform the category of “idiopathic” autism into subtypes that can be described based on shared biology.
Why study autism subtypes?
If we succeed in finding and defining autism subgroups based on shared biology, it could revolutionize the way we think about the condition. For example:
* Studying certain subgroups may enable us to understand the cause of autism’s many associated medical conditions.
* Studying other subgroups may help us find people who respond better – or worse – to experimental medications for autism’s core symptoms.
* Studying still other subgroups may enable us to identify gene changes that increase – or decrease – vulnerability to the environmental factors that predispose to autism.
By identifying and characterizing multiple “autism biologies,” we hope to usher in a new way of thinking about autism that leads to a new era of highly fruitful research.
In closing, I’d like to offer a couple of quotes to ponder …
"For every complex problem there is a solution that is concise, clear, simple … and wrong."
- H.L. Mencken (1880 - 1956), journalist, essayist and editor
“Fortunately, solutions that account for complexity are now within reach.”
-D.S. Tylee (1987 – present), aspiring physician-scientist, autism researcher and blogger
Read about more ground-breaking research by Autism Speaks Fellows in the Science@Work archives here.