A leading WA autism researcher says a new US study has added weight to a theory linking autism to gut problems that could be treated.
Scientists have found a link between mice with gastrointestinal problems caused by changes in bacteria in the gut and autism-type behaviour.
Their results, published in the medical journal Cell, also found that giving affected mice so-called good gut bacteria helped problems such as anxiety-like behaviour disappear.
Researchers from the California Institute of Technology said several studies had shown that bacteria known as microbiota could affect social and emotional behaviour, including anxiety.
Their findings linked some symptoms of autism to the gut and suggested that probiotics might help treat them.
Clinical trials were now needed to verify the effects found in mice.
"These findings identify a potential probiotic therapy for gastrointestinal and behavioural symptoms in human disorders, including autism," the researchers concluded.
They said it was also thought that mice whose mothers suffered from infection or inflammation during pregnancy were at greater risk of developing behaviour similar to those seen in people with autism.
Professor Andrew Whitehouse, head of the Telethon Institute for Child Health Research's Developmental Disorders Research Group, said the link between maternal inflammation and autism - and between gut problems and autism - had long been suspected but the study had started to put pieces of the puzzle together.
"Importantly, when the researchers gave the offspring an oral dose of normal bacteria, or the bacteria that a normal gut usually contains, the behavioural symptoms of autism disappeared," he said.
"This is an exciting study that provides preliminary evidence for a potential causal pathway that has long been suspected."