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Genetics and the environment

Autism is traditionally labeled as a development disorder. It affects information exchange in the brain by altering how nerve cells and synapses (signal bridges between cells) connect.

By the criteria outlined in the American Psychiatric Association's Diagnostic and Statistical Manual (APA DSM) IV, the disorder displays three general hallmarks: 1) an impairment of social interaction, 2) an impairment of communication, and 3) restricted or repetitive behavior or interests. It normally manifests before the age of three.

The disorder doesn't necessarily affect learning, however. "Autists are incredibly teachable children," Men told The Moscow News. "They are children who, connected with some concrete situation, have trouble communicating their needs. [The symptoms] are very individual."

Though the condition exists in a broad range of permutations - often called the autism spectrum - autistic individuals are unable to fully verbally express themselves in a conventional way. They can have difficulty building and maintaining close relationships. In some cases, they develop obsessive habits like arranging objects in a particular way or pattern.

The disorder's origins, though extensively researched, are still largely unknown. Scientists have established a definite genetic link, but social and environmental factors are also thought to contribute.

"The current thinking about many, but not all, people in the autism community is that many... forms of autism are the result of an interaction between genetics and the environment," said Stephen Edelson, director of the California-based Autism Research Institute, to The Moscow News.

According to Edelson, some of the possible environmental causes being researched are pesticides and heavy metals. "We also realize that some forms - estimated to be about 20 percent - are purely genetic," he said. "[But] there is still much more we need to know about the underlying causes."

Childhood abuse of the mother may also contribute. JAMA Psychiatry published a research report in March which stated that women who were brought up under the "highest level of abuse" were three times more likely to bear an autistic child.


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