A NEW genetic link to autism has been discovered by scientists, raising hopes for sufferers and their families.
Researchers in the United States found that a variation in a gene known as CNTNAP2 appeared to increase the risk of developing autism.
The discovery is the latest piece in the genetic jigsaw as scientists search for links which could help devel
op new autism treatments.
In recent years, several studies have highlighted the important role genes are likely to play in the development of autism.
Several teams of researchers, writing in the American Journal of Human Genetics, have used different methods to pinpoint a genetic variation in children with autism, making the findings even more robust.
Researchers from groups including Johns Hopkins University and the National Institute of Mental Health (NIMH) studied two groups of children – together making one of the largest autism studies ever conducted. The first stage involved 145 children with autism and their parents from families with two or more autistic youngsters.
They found a chromosome called 7q35 was linked to autism , and through this they identified a variant in the CNTNAP2 gene.
A larger study, involving 1,295 children with autism and their healthy parents, also found levels of the genetic variant higher than would be expected by chance. Researchers found autistic children were 20 per cent more likely to have inherited the variant from mothers than their fathers.
But they pointed out that inheriting the gene variant did not mean a child would inevitably develop autism, but it did mean they may be more vulnerable to developing the condition.
Thomas Insel, NMIH director, said: "Identifying the genes involved is crucial in our ability to map out the pathology of this isolating and sometimes terribly disabling disease, which currently has no cure."
Another study by the University of California Los Angeles, also identified the gene variant and the link with autism. It found the gene was most active in the parts of the brain involved with language and thought.
Dr Daniel Geschwind, one of the researchers, said: "This gene not only may predispose children to autism, it may also influence the development of brain structures involved in language, providing a tangible link between genes, the brain and behaviour."
Stewart Gunn, from the Scottish Society for Autism, said they welcomed any new research into causes of autism which might lead to new treatments.
