Searching for the cause of autism

Scientists are a step closer to finding what gives our children autism and television could be a factor. Researchers have shown early exposure to TV may be a trigger for the disorder and the screen has also been linked to short-sightedness and the early onset of puberty.

Psychologist Dr Aric Sigman has published a report that analyses 35 scientific studies and it identifies 15 negative effects of television. He said the average six-year-old child in Britain will have spent one full year watching television and over half of three-year-olds have a TV set in their bedroom Dr Sigman said: "To allow children to continue to watch this much screen media is an abdication of parental responsibility, truly hands-off parenting."

In a separate study two genetic factors have been identified as the possible root of autism.

More than 120 scientists from 19 countries have been working on the Autism Genome Project, the largest-ever study into the genetic causes of the disorder. They have found a region of chromosome 11 could be linked to autism and a gene called neurexin 1 could also be implicated. The researchers said their findings add to the evidence that tiny, rare variations in genes may heighten the risk for autism spectrum disorders.

For the study, published in the journal Nature Genetics, researchers used two techniques to examine the DNA of the families with a history of autism. So-called "gene chip" technologies were used to look for genetic similarities among affected families.

In addition, scientists scanned the same DNA to look for variations in the make-up. The AGP researchers found a number of variations in the genetic material of people with autism.

Bernie Devlin, an associate professor of psychiatry and human genetics at the University of Pittsburgh in the US, said: "This project represents a new beginning in autism research, and provides an invaluable resource to researchers worldwide. We hope that access to the tools and information developed through this project will help researchers begin to unravel the causes of autism."

In the UK, work was carried out at the University of Manchester, the Institute of Psychiatry at King's College, London, and the University of Oxford. Child psychiatrist Professor Jonathan Green, who led the Manchester team, said: "Autism is a very difficult condition for families - communication is taken for granted by parents of healthy children but is so greatly missed by those with autistic children. We are working now in Manchester to investigate the basic science and develop and test new treatments for the condition. We hope that these exciting results may represent a step on the way to further new treatments in the future."