Scientists have found the biological patterns that will enable autism to be diagnosed in children as young as 12 months.
Research into mapping gene networks that disrupt brain cell production will be presented to the Asia Pacific Autism Conference in Adelaide today.
The discovery represents a major breakthrough in autism research and is the basis for a blood screening test currently being developed.
Autism affects about one in every 100 children with varying severity, but identifying the early signs can be tricky.
A professor of neurosciences at the University of California, Eric Courchesne, says his new research will advance the field.
"For years I've wondered what might be the systems that cause autism to come about in the first place, and I have to say, this is a very exciting finding," he said.
He says the sooner a child is diagnosed with autism, the better the outcomes from treatment.
"By coming up with early detection and early screening methods, it will eventually be possible to detect and diagnose autistic kids at a much younger age, perhaps one or two years old instead of at three, four or five," he said.
"That means they'll get treatment earlier, which means they'll have a better outcome."
Professor Courchesne says his research measures the genetic network itself rather than a gene.
"A gene is a possibility, it's a blueprint for building or doing something, but it's the actual activity of translating that blueprint into a building that really is more like what we're measuring," he said.
"This is the very first brain gene discovery. It tells us something about what gene systems may be important for future research into treatments, into the development of early markers for autism and so forth."
Professor Courchesne says the genetic network research is accurate for detecting autism.
"It identifies roughly about 80 to 85 per cent of infants and toddlers that are at risk for autism and it makes it possible for the first time to identify potentially a very large percentage of kids if it turns out that we can replicate our findings," he said.
He hopes further research into the gene networks that can cause autism will not only result in a better understanding of the disorder, but may one day lead to its prevention.