How can I find out what caused my child’s autism?
In most individuals it is currently not possible to identify the exact cause of autism. There are a few genetic syndromes associated with autism (for example, Rett syndrome and fragile X syndrome) in which the genetic cause is known. Scientists have also identified a number of rare genetic changes that are major contributors to autism. In about 25 percent of autism cases, a specific genetic cause can be identified. The remaining 75 percent of cases likely involve a complex combination of genetic factors and yet-to-be identified environmental influences. At this time, there is no evidence that specific chemicals in the environment, immunisation practices or dietary differences cause autism.