The largest genome study of autism to date sought to investigate the genetic code behind autism, and found 18 new genetic variations that increase risk for the condition. The study was part of the Autism Speaks ‘MSSNG’ project, and was published Monday in the journal Nature Neuroscience. Overall, that project has identified 61 genetic variations linked to autism risk.
The new study examined more than 5,000 genomes from entire families who have been affected by autism. It sheds light on the range of subtypes of autism, which they hope to identify, and use to better target treatments for individuals. A better understanding of this could also help scientists explain the biology that causes autism.
The range and variation identified by the research attests to the “spectrum” nature of autism, including a wide range of symptoms and underlying genetics.
According to Dr. Mathew Pletcher, who is the vice president of genomic discovery at Autism Speaks:
“[The study] helps underscore…the incredible variety, the heterogeneity, in what autism is. This diagnostic category of autism is one that covers so many unique genetic backgrounds and unique biologies, and yet it’s all being considered as one thing. But in reality, with each new study we do and each new gene we find, we’re seeing that in fact autism is collecting together this huge group of really complex genetic traits.”
Research like this could one day allow for more specific definitions of the conditions on the autism spectrum, which in turn could lead to treatments better targeted to individuals.
The researchers collaborated with Verily, the life science division at Google, to store the massive quantity of data on Google Cloud. They analyzed all 3 billion DNA pairs making up each of the 5,000 genomes of the individuals in the study.
Beyond just genetic mutations, the research found a range of genetic causes for autism, including chromosomal abnormalities and repeated and deleted genes. Pletcher added that several of the 18 newly identified genes are considered “druggable,” which means scientists are able to create molecules that interact with, and change the functioning of, the proteins generated by the genes. The authors of the study estimated roughly 80 percent of the 61 genes that have been discovered could potentially be targets for medication.
Several of the genes linked to autism were also related to medical problems known to accompany autism, such as seizures and adult-onset diabetes. This discovery could become important to preventative care and early diagnosis.
The genetic variations, according to the researchers, fit into three separate “pathways,” networks of genetic mutations. One of the three, for example, is made up of variations that affect the way neurons communicate with each other and develop. These pathways could allow for medications that treat all of the variations that make up a given pathway, according to Pletcher.