Autism can be linked to certain abnormalities in genes, an autism researcher from University of Gothenburg, Sweden has found.
Christopher Gillberg and his team revealed that that Copy Number Variants (CNVs) - sub-microscopic abnormalities in the chromosomes - are heavily over-represented in autistic people.
"Some of these are inherited, while others have appeared for the first time in the person with autism," said Gillberg.
"Several of the abnormalities affect the genes that we have previously shown to be linked to autism and psychological developmental disorders," he said.
Gillberg and his colleagues had been asserting for a long time that although genetic abnormalities occur in just a small number of autistic people, they together account for an increasing proportion of all cases, and that autism is an umbrella term for a large number of different neurobiological conditions that have the same symptom picture.
The study also provides evidence that other genes that are important for synapse development and intra-cellular communication (communication between the nerve cells) play a role in the origin of autism in some cases.
The study is published in Nature.