Autism Facts
A Definition
Causes
Red Flags
Frequency
Fast Facts
Rain Man
Beginnings
Notable Sufferers
Vaccine Controversy
 Causes
Previous Next


 (Photo: CBS/AP)

Brain scans show differences in the shape and structure of the brain in autistic versus non-autistic children.

Researchers are investigating a number of theories, including the link between heredity, genetics and medical problems.

In many families, there appears to be a pattern of autism or related disabilities, further supporting a genetic basis to the disorder. 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 unstable 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 environmental chemicals.