Urine samples could one day be used to test whether children are on the autistic spectrum.
This is the suggestion of scientists from Imperial College London and the University of South Australia.
The researchers have looked into the different makeup of bacteria in the guts of children who are on the autistic spectrum and of children who are not.
It was revealed that the differences could be detected in the by-products of the digestive system.
Professor Jeremy Nicholson, corresponding author of the study, commented: "Autism affects many different parts of a person's system and our study shows that you can see how it disrupts their system by looking at their metabolism and their gut bacteria."
He added: "We know that giving therapy to children with autism when they are very young can make a huge difference to their progress. A urine test might enable professionals to quickly identify children with autism and help them early on."