Scientists have identified a genetic pattern common to people with autism that is linked to the way messages are sent in the brain.

Medical Research Council (MRC) researchers at the University of Oxford said the knowledge could help them understand the role genetics plays in autism.

Doctors can only identify the exact genetic cause of autism in about one in five cases but it is known that genes play an important role in the development of autism spectrum disorders, an MRC spokeswoman said.

A total of 181 autism patients who either had additional copies of some genes, or fewer copies, than those without autism were studied. In about half of the patients, the affected genes worked together as part of a biological network involved in the way information passes between brain cells.

Autism spectrum disorders affect about 1% of the population.