An international team of researchers have been looking into the genetic factors behind autism. They looked at the DNA of more than 12,000 people, some from families affected by autism and others from unaffected volunteers. The team of researchers found a series of genetic variations which, they believe, could account for as many as 15% of cases of autism. Most of the genes are involved in synapses - the connections between brain cells - and although these variations are common in the general population they occur about 20% more often in children with autism. This is the first time there has been such good evidence linking a set of genetic variations to autism.
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