22 August 2017
New brain-related mutations linked to autism spectrum disorder
Published online 19 July 2017
Researchers have identified non-inherited mutations prevalent in individuals with autism.
An international consortium has identified new mutations linked with autism spectrum disorder, improving our understanding of the disease and potentially guiding therapeutic approaches.
The team, which included researchers at the King Abdulaziz University in Saudi Arabia and the Mohammed Bin Rashid University of Medicine and Health Sciences in the UAE, reanalysed data from earlier studies which had sequenced DNA from 5,947 individuals with or without autism spectrum disorder (ASD) and from both of their parents1.
The new analysis revealed 4,846 de novo mutations in the data. Using a custom pipeline, which they had developed, the team showed that 468 of these were postzygotic mutations — mutations that occur in an individual’s body rather than being inherited from their parents.
“Understanding postzygotic mutations can teach us about the brain regions that are involved in a disease, as well as the specific cell types and mechanisms involved,” says Elaine Lim of Boston Children’s Hospital, the study’s lead author. “Studying them is a way for us to understand more about the mechanisms in some kids with ASD.”
The postzygotic mutations in the autism patients were concentrated in critical portions of genes expressed in the brain, especially in the amygdala, a brain region involved in emotional and social responses. The team also identified 27 genes that were consistently affected by postzygotic mutations in autism patients, including several that have already been linked with autism or other neurodevelopmental disorders.
“Our findings have highlighted specific developmental times and brain regions that might be important in ASD, and targeted therapeutic approaches can be designed based on this understanding,” says Lim.
The team is also collaborating to use their pipeline to identify postzygotic mutations involved in other conditions, such as epilepsy and schizophrenia.
- Lim, E. T. et al. Rates, distribution and implications of postzygotic mosaic mutations in autism spectrum disorder. Nat. Neurosci. http://dx.doi.org/10.1038/nn.4598 (2017).