The genomes of the largest collection of families with multiple cases of autism ever assembled have been scanned and the preliminary results published in Nature Genetics. They provide new insights into the genetic basis of autism.
The research was performed by more than 120 scientists from more than 50 institutions representing 19 countries. In the UK, work was carried out at The University of Manchester, the Institute of Psychiatry at King's College, London and the University of Oxford.
The international collaboration started in 2002 when researchers from around the world decided to come together and share their samples, data, and expertise to facilitate the identification of autism susceptibility genes. They formed the Autism Genome Project.
The world-wide consortium of scientists made the most of its large sample of 1,200 families, using "gene chip" technology to look for genetic similarities in autistic people. The AGP also scanned DNA from these families for copy number variations (CNV), or sub-microscopic genomic insertions and deletions that scientists believe might be involved with this and other common diseases.
The innovative combination of these two approaches implicates a previously unidentified region of chromosome 11, and neurexin 1 - a member of a family of genes believed to be important in the contact and communication of neurons. 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 first phase of the effort – the assembly and scanning of the largest autism DNA collection ever – was funded by Autism Speaks, a non-profit organisation dedicated to increasing awareness of autism and raising money to fund autism research, and the US National Institutes of Health.
Phase two of the project, which will build on the success of the linkage scan, is now being launched. It represents a £7.44 million investment over three years by Autism Speaks, the UK Medical Research Council (MRC), the Health Research Board of Ireland (HRB), Genome Canada and partners, Canadian Institutes for Health Research (CIHR), Southwest Autism Research and Resource Center (SARRC), and the Hilibrand Foundation. This unique combination of international, public and private partners funding a consortium of clinicians and scientists is unprecedented in the field of autism research.