Autism genes linked to higher intelligence

A new study has suggested that genes linked with a greater risk of developing autism may also be associated with higher intelligence.

Universities of Edinburgh and Queensland researchers said that the relationship between autism and intelligence is not clear, adding that although up to 70 per cent of individuals with autism have an intellectual disability, some people with the disorder have relatively well-preserved, or even higher than average, non-verbal intelligence.

The team found that even among people who never develop autism, carrying genetic traits associated with the disorder is, on average, linked to scoring slightly better on cognitive tests.

Researchers found further evidence of a link between autism-associated genes and intelligence when they carried out the same tests on 921 adolescents who were part of the Brisbane Adolescent Twin Study.

Lead author Toni-Kim Clarke said that the findings show that genetic variation which increases risk for autism is associated with better cognitive ability in non-autistic individuals.

Clarke added that as they begin to understand how genetic variants associated with autism impact brain function, they may begin to further understand the nature of autistic intelligence.

Researcher Nick Martin said that links between autism and better cognitive function have been suspected and are widely implied by the well-known "Silicon Valley syndrome" and films such as "Rain Man" as well as in popular literature.

Martin added that this study suggests genes for autism may actually confer, on average, a small intellectual advantage in those who carry them, provided they are not affected by autism.

The study is published in the journal Molecular Psychiatry.