Causes
There is no known single cause for Autism Spectrum Disorder, but it is generally accepted that it is caused by differences in brain structure or function. Brain scans show differences in the shape and structure of the brain in Autistic children compared to neurotypical children. Researchers do not know the exact cause of Autism but are investigating a number of theories, including the links among heredity, genetics and medical problems. In many families, there appears to be a pattern of autism or related disabilities, further supporting the theory that the disorder has a genetic basis. While no one gene has been identified as causing autism, researchers are searching for irregular segments of genetic code that Autistic children may have inherited. It also appears that some children are born with a susceptibility to Autism, but researchers have not yet identified a single “trigger” that causes Autism to develop. Other researchers are investigating the possibility that under certain conditions, a cluster of genes may interfere with brain development, resulting in Autism. Still other researchers are investigating problems during pregnancy or delivery as well as environmental factors such as viral infections, metabolic imbalances and exposure to chemicals.
Genetic Vulnerability
Autism tends to occur more frequently than expected among individuals who have certain medical conditions, including fragile X syndrome, tuberous sclerosis, congenital rubella syndrome and untreated phenylketonuria (PKU). Some harmful substances ingested during pregnancy also have been associated with an increased likelihood of Autism.
At the Autism Society of Oregon, our focus is not on the cause or causes of Autism, but how we can help Autistic individuals and their supporters find and access the resources they need, when they need them.