The Globe and Mail
By looking at all the available genetic data on autism – the genomes of 3,000 North American and European families – the scientists figured out a formula for calculating the genetic probability that a person has autism spectrum disorder.
The genes that contain variations that lead to autism are turned on during prenatal development. “We’ve stumbled upon the core group of genes that is necessary for human cognition,” said Stephen Scherer, senior scientist at Sick Kids Hospital and lead author of the study published Sunday in Nature Genetics…..
the findings suggest that autism genes are active early in the development of the brain, they will help address the clinical demand for a diagnostic test for very young children. As many as one in 68 children are diagnosed with autism spectrum disorder, most after the age of four, but the sooner the intervention, the better the outcome for these kids.
Everyone has genetic variations, called mutations among scientists, but researchers have had difficulty determining which variations lead to autism. To overcome this obstacle, the autism research community compiled a list of autism risk genes, or genes that exist in many unrelated people with autism but that don’t generally exist in people without autism. There are so many possible variations within these listed genes that, unless an identical and known variation is found, it’s impossible to know what impact this variation will have with respect to autism. Current genetic diagnostic testing considers around 100 genes but we don’t know exactly what autism symptoms these genes are associated with.
For example, SHANK3 is a gene that is often involved in autism testing. If there is a mutation in one area of the gene, it will cause autism – but if a mutation occurs in another area of the same gene, it won’t.