One of the big questions in autism research is whether autism is a single disorder or many different disorders that happen to present in the same way. Although recent genetic research has indicated hundreds of different genes contribute to autism, a new discovery has found there could also be commonality among most patients with autism.
Autism is characterised by a certain pattern of social communication and social interaction skills and repetitive and restricted behaviours that differ from the rest of the population. Symptoms can range from mild to severe.
We know from studies of twins, and observations within families, autism has a large genetic component.
However, despite there being hundreds of autism-associated genes known to us, most have a very small effect on whether or not someone will have autism. There are also no genetic tests that can diagnose autism.
Recently, researchers started studying the environmental contributions to autism: the other side of the nature-nurture coin. They looked to events as far back as the womb.
Listen to our parenting podcast about being diagnosed with autism later in life. (Post continues after audio.)
Looking beyond the DNA sequence, we know both genetic factors and environmental factors such as diet, stress and pollution can change the switches that switch our genes on and off.
We call these switches “epigenetics,” and when we study them, we are measuring the molecules that change these switches.
Epigenetics and autism
In autism, we can study the pattern of these epigenetic switches (which are turned on and off) and compare the pattern to that seen in people without autism. In this way we can better understand the causes of autism, and may one day be able to diagnose autism much earlier or pinpoint environmental factors that can be avoided.
Ultimately, we want to improve the quality of life for people living with autism and provide their families with timely assistance.
In 2015 my colleagues and I reviewed recent studies that had searched for the epigenetic switches specific to autism. Although the field was in its infancy, there was a small number of switches that had been identified as being closely linked to autism. However, this knowledge was not yet ready for use in the clinic.