Scientists have literally found the needle in the haystack as years of scientific slogging and cutting-edge technology coupled to help to discover hitherto unknown genetic material that causes autism.
The discovery expected to do much in the prevention and treatment of autism has been met with considerable excitement and speculation.
Scientists, all part of an international team from 8 countries and led by Canadian researchers of Toronto's Hospital for Sick Children and the Offord Centre for Child Studies scanned the entire human genome for autism related genes.
The consortium of scientists, 137 from 50 centres worldwide that make up the Autism Genome Project, analyzed DNA from about 1,600 families with autistic children to try to zero in on a specific group of brain cells and the genes that affect their development and function.
Unlike previous research which identified chromosome numbers 2, 7 and 17 to be involved in autism, the scientists were surprised to see another chromosome, number 11 play the key role in autism.
One of its genes was discovered- neurexin 1, part of a family of genes believed to play a part in neuron communication during brain development.
The results are published in Nature Genetics.
Children with autism (80 percent are males) have difficulty interacting and communicating with others including family members. They often exhibit repetitive behaviors such as rocking back and forth, flapping their hands or hitting themselves. The complex disorder affects about one in 165 children, making it the most common form of childhood neurological disorder or developmental disability.
According to co-author Dr. Stephen Scherer, a senior scientist in genetics at Sick Kids, genome-scanning methods were used to test genetic markers for autism and the same procedure followed to find regions in the genome that were linked autism causing genes.
Co-author Dr. Peter Szatmari, director of the Offord Centre for Child Studies, said the discovery has huge implications for autistic patients and their families in the future.
According to Dr. Robert Hegele, a professor of medicine and biochemistry at the University of Western Ontario the research suggests there are many different forms of genetic susceptibility in autism.
Isolating those areas could one day allow for a test that would confirm the autism diagnosis in children exhibiting symptoms and tell family members whether they, too, carry the combination of genetic defects that could be passed on to their children, he added.