Many of these genes play a role in biological pathways that affect how brain cells develop and communicate with one another.
'Eighty percent of them involve common biological pathways that have potential targets for future medicines, ' said Dr Ryan Yuen, research associate at The Hospital for Sick Children, Toronto, and one of the leaders of the study.
Other types of genetic changes, including CNV (copy number variation) and chromosomal abnormalities, were also found to be associated with ASD. Many of the CNVs were found in areas of non-coding DNA that help control when and where genes are switched on and off. This precise coordination of genetic activity appears to be important for brain development and function.
The study came out of the Autism Speaks MSSNG Project, which has sequenced the DNA of over 10,000 families affected by ASD since 2014. This data is housed on a research platform on Google Cloud and is freely accessible to autism researchers around the world.
Some of the genetic variations identified in the study occurred in families with one person severely affected by autism, while others occurred in those on the milder end of the spectrum.
'This reinforces the significant neurodiversity involved in this complex condition,' said Dr Stephen Scherer, director of the Centre for Applied Genomics at The Hospital for Sick Children, Toronto, and senior investigator of the study.
'In addition, the depth of the MSSNG database allowed us to identify resilient individuals who carry autism-associated gene variations without developing autism,' he added.
As its name suggests, the MSSNG project aims to address current knowledge gaps and identify subtypes of autism. It is hoped that this will lead to the development of more personalised and more effective treatments.
The study was published in Nature Neuroscience.