One of the most common questions asked after a diagnosis of autism, is what caused the disorder. We know that there's no one cause of autism. Research. Although sometimes cited as a cause of autism, there is no evidence that vaccinations cause autism. The exact reason why autism happens isn't clear. Research. Does a friend or family member have a child with autism? Autism rates seem to be skyrocketing. Among children who are 8 years old, autism has nearly doubled .
Causes Autism? What
For example, an epidemiological study led by QBI Professor John McGrath found that women deficient in Vitamin D during pregnancy had children with an increased risk of autism. A lack of Vitamin D is just one risk factor, but it can also interact with other environmental variables. Associate Professor Thomas Burne , for example, is looking at how Vitamin D deficiency can combine with low levels of alcohol during pregnancy to raise the risk of autism-like behaviours in mice.
Another environmental risk is viral or bacterial infection of the pregnant mother during the first trimester, which has become a common way to study autism in model animals like mice. The laboratory of Professor Darryl Eyles has shown that the presence of Vitamin D protects against autism-like behaviours that are triggered by infections of the mother.
The work of Professors McGrath, Eyles and Burne converges in the long-term hope that by supplementing pregnant mothers with Vitamin D, autism rates might be reduced. In the developing brain, connections between and within brain regions are still being formed.
One example relevant to autism is a congenital condition called agenesis of the corpus callosum AgCC. The corpus callosum is a thick bundle of nerve fibres that connects one brain hemisphere to the other. In people with AgCC, the corpus callosum is partly or even completely missing.
Strikingly, one third of patients with AgCC meet the diagnostic criteria for autism. Other studies, however, have found the opposite profile in some people with autism — an enlarged corpus callosum. How can these findings be reconciled? According to Professor Elliott Sherr of the University of California, San Francisco, who has teamed up with Professor Richards, one possibility is that autism could result from inefficient communication between brain hemispheres, and that efficiency could be disrupted whether the corpus callosum is too big or too small.
Autism signs and symptoms. Help QBI research Give now. Skip to menu Skip to content Skip to footer. Some of these include:. What are the symptoms of autism? When do children usually show symptoms of autism? How do health care providers diagnose autism? What are the treatments for autism? Share Facebook Twitter Pinterest Email. Scientists don't know exactly what causes autism spectrum disorder ASD.
Scientists are studying some of the following as possible causes of or contributors to ASD. Interactions between Genes and the Environment. Some of these include: Problems with brain connections Problems with growth or overgrowth in certain areas of the brain Problems with metabolism the body's energy production system Problems in the body's immune system, which protects against infections.
Exploring the environmental contribution. Current Opinion in Pediatrics, 22 2: Genetic heritability and shared environmental factors among twin pairs with autism. Archives of General Psychiatry, 68 11 , — Common gene variants account for most genetic risk for autism. Retrieved March 2, , from https:
Autism Spectrum Australia
Many causes of autism have been proposed, but understanding of the theory of causation of autism and the other autism spectrum disorders (ASD) is incomplete . These articles discuss some of the possible causes of autism, and some thoughts on the concept of a 'cure'. One of the great and enduring mysteries of autism is what causes the brain to develop so differently.