[img_inline align=”right” src=”http://padnws01.mcmaster.ca/images/Szatmari, Peter1.jpg” caption=”Dr. Peter Szatmari, director of the Offord Centre for Child Studies and head of the Division of Child Psychiatry at McMaster. Photo courtesy of FHS. “]Researchers at the Offord Centre for Child Studies at McMaster University have led an international consortium in the discovery of genes that may contribute to a child's risk of developing autism.

Their findings, based on genetic samples from nearly 1,200 families with two or more children who have autism, were published today in the journal Nature Genetics.

Led by Dr. Peter Szatmari, director of the Offord Centre, and Dr. Stephen Scherer at The Hospital for Sick Children, the Canadians are part of the largest genome scan ever attempted in autism research. Their work is supported by Genome Canada and the Canadian Institutes of Health Research.

More than 120 scientists from Europe and North America make up the Autism Genome Project, which was launched in 2002 to share data, samples and expertise in an effort to speed up the process of identifying susceptibility genes that heighten a child's risk of having the developmental disorder.

Using this unprecedented statistical power, the scientists were able to implicate a previously unidentified region of chromosome 11 and neurexin 1, among other regions and genes in the genome. The neurexin finding in particular highlights a special group of neurons, called glutamate neurons, and the genes affecting their development and function, suggesting they play a critical role in autism spectrum disorders.

“The clinical implications of this discovery are unprecedented,” said Szatmari, who led the committee to decide the phenotypes to be used in analysis, and was instrumental in drafting the memorandum of agreement among the consortium members, who represent 50 institutions. “Not only have we found which haystack the needle is in, we now know where in the haystack that needle is located. This is a major breakthrough in our efforts to better understand the disorder and improve diagnosis and treatment for patients and their families.”

A professor, vice-chair of research, and head of the Division of Child Psychiatry at McMaster, Szatmari is a leading expert in autism, one of a number of developmental problems studied by researchers at the Offord Centre. He and other members of the Centre's autism team have been responsible for some of the most exciting recent developments in the field of autism research worldwide.

Autism is a complex developmental disorder affecting roughly one in 165 children, making it the most common form of any childhood neurological disorder or severe developmental disability. Those affected exhibit severe impairments in reciprocal social interaction and communication, and a preference for repetitive, stereotyped behaviours.