Skip to content
Olga Tennison Autism Research Centre
  • OTARC Website
  • Our Researchers
  • Studies Recruiting
  • Early autism detection app
  • Donate
Ask an Autism Researcher

Is there an environmental cause of autism?

  • June 6, 2018

Recognition has grown over the past decade that aspects of our environment may also contribute to autism. However, despite substantial research, no one environmental factor has yet been found to be a definite cause of autism.

The most widely used research technique to examine environmental risk factors for autism is epidemiology, which examines how often, and why, diseases occur in different groups of people.

Several environmental factors during prenatal life have been linked with autism. Bacterial or viral infections in the mother during pregnancy have been found to slightly increase the risk of autism in the offspring. This could be due to the passage of harmful infectious organisms from the mother to the fetus through the placenta, or because the immune response of the mother may be detrimental to the developing brain of the fetus.

Other factors in the mother that may be related to offspring autism include a folic acid deficiency at the time of conception, the presence of gestational diabetes and the use of certain antidepressants during pregnancy, but no conclusive evidence exists for any of these links.

Being an older parent, particularly an older father, is also thought to increase the risk of having a child with autism. As males get older, the number of sperm that contain de novo genetic mutations increases.

Some of the de novo genetic mutations will have minimal or no effect on the resulting baby, but some mutations can lead to the brain developing differently.

Several studies have found that fathers who are over 50 at the time of conception have a greater chance of passing on de novo mutations and also a greater risk of having a child with autism.

An obvious, but very important, observation is that not all people who are exposed to these factors are diagnosed with autism. One possible explanation for this is a phenomenon called gene-environment interaction, which is when the genetic make-up of two different people leads them to respond differently to an environmental factor.

by Andrew Whitehouse, Winthrop Professor, Telethon Kids Institute, University of Western Australia

This is an excerpt of an article originally published on The Conversation. Read the original article.

Share

Share this:

  • Click to share on Twitter (Opens in new window)
  • Click to share on Facebook (Opens in new window)

Related

Talk: Marking 10 Years of Autism Research
Does the brain develop differently in those with autism?

Articles

  • Latest research findings
  • Mental Health
  • Autism Girls and Woman
  • Neurodiversity
  • Ask an Autism Researcher
    • Adults with autism
    • Autism and sleep
    • Autism and the senses
    • Autism therapies & treatments
    • Autism, speech & language
    • Causes of autism
    • Family wellbeing
    • Intellectual disability and autism
    • Teaching and learning with autism
  • Frame of Mind artists
  • Inside the Lab
  • News
    • Director's Report
    • Events
  • Studies Recruiting

Search

Join a Research Study

  • Register with OTARC

Subscribe to our Newsletter



    Social

    Friend me on Facebook
    Follow me on Twitter
    © 2018 Olga Tennison Autism Research Centre
    Theme by Colorlib Powered by WordPress
    • Register with OTARC