A new study that used genetic data from nearly 43,000 autistic individuals and their families has identified 60 autism spectrum-associated genes with exome-wide significance, including five new genes not previously implicated in neurodevelopmental disorders.  

University of Iowa scientists led by Jake Michaelson, PhD, associate professor of psychiatry in the UI Carver College of Medicine, contributed to the new study, which was published recently in Nature Genetics.  

“We’re really excited about this study because it sheds light on how genes are influencing the brain over a wider band of the autism spectrum,” says Michaelson, who also is a Roy J. Carver Associate Professor of Psychiatry and Neuroscience and a member of the Iowa Neuroscience Institute.  

Previous studies involving millions of people have already shown that autism is mostly heritable, but those studies stopped short of identifying specific genes and mechanisms involved in autism. Other research that has identified specific genes strongly associated with autism has focused on new or “de novo” mutations found in the genome of a child with autism but not inherited from their parents’ genome. These de novo mutations are usually also associated with intellectual disability. However, most autistic individuals do not have this type of mutation, so they only represent a small part of the genetic picture.  

In contrast, the new study focused on rare genetic variations that are inherited by the child with autism from a parent who does not have autism.  

“We found that these inherited variants are less associated with intellectual disability, and they expand our view of what developmental mechanisms are being impacted in autism,” Michaelson says. “Ultimately this knowledge will help us better understand subtypes of autism that each have different support, resource, and treatment needs.”