Environmental Factors in Autism

The role of environmental factors in the development of autism is a crucial area of study. We know that genetics strongly influence the risk for developing autism spectrum disorder (ASD). However, genetics alone do not account for all instances of autism. For good reason, the increasing prevalence of autism has generated great interest in the potential involvement of toxins in our environment. For example, prenatal exposure to the chemicals thalidomide and valproic acid has been linked to increased risk of autism.

Learn More About Avoiding Toxic Exposures During Pregnancy

It's important to understand that the study of environmental risk factors includes much more than exposure to chemicals. Scientists use the term "environmental" to refer to influences other than changes in a gene’s DNA. Autism risk factors, for example, appear to include such influences as parental age at conception, maternal nutrition, infection during pregnancy and prematurity.

Autism Speaks Environmental Factors in Autism Initiative targets research that can advance our understanding of the environmental influences that increase – or decrease – autism risk. None of these influences appears to “cause” or “prevent” autism by themselves. Rather they appear to influence risk in those genetically predisposed to the disorder.

Environmental Research Supported by Autism Speaks
Autism Speaks remains strongly committed to advancing the understanding of both genetic and environmental risk factors for autism. One important area of research concerns how environmental influences interact with genetic susceptibility. Such research is crucial for guiding prevention and improving diagnosis and treatment. 

To date, Autism Speaks has released two requests for applications (RFAs) to support research on environmental risk factors. The first, in 2008, supported 12 studies. Some delved into the role of the immune system and epigenetics, the study of factors that control gene activity. Others advanced animal models for the study of chemicals newly suspected of increasing autism risk.

Also in 2008, Autism Speaks announced a groundbreaking collaboration between two Autism Centers of Excellence. This collaboration is expanding the collection of genetic and environmental information in two large groups of families affected by autism. Autism Speaks is supporting the collection of information on environmental exposures in mothers and children for all participants in both studies. (Read more about this project here.)

Please also see our Environmental Grants overview page and for information on applying for an Autism Speaks research grant, please visit our Open Grants page.

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