Preliminary findings from the first phase of the largest-ever autism genome scan were published in the online edition of , one of the world's most prestigious research publications, on Feb. 18. This research was performed by more than 120 scientists from more than 50 institutions representing 19 countries who formed a first-of-its-kind autism genetics
consortium, the Autism Genome Project (AGP). Cure Autism Now's Autism Genetic Resource Exchange (AGRE) contributed one-third of the clinical data and DNA samples analyzed by the AGP in this study.
The AGP began 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. The first phase of the effort, the assembly of the largest autism DNA collection ever and whole genome linkage scan, was funded by Autism Speaks and the U.S. National Institutes of Health. The launch of phase two of the project, building on the success of the linkage scan, is being announced on Feb. 28.
While AGP is a model of unprecedented collaboration, programs such as AGRE provided the basis for launching such an ambitious and productive effort. Cure Autism Now founded AGRE in 1997, and families across the country have contributed to this vital resource. With the large number of families participating via AGRE and other gene and data banks, the researchers have been able to focus their efforts by looking at different groups of data with similar characteristics, and the corresponding DNA.
"The large number of families in this study permitted us to organize autistic children with similar features of this disorder into smaller groups, where gene linkages may be more easily detected," says Rita Cantor, professor of human genetics at the David Geffen School of Medicine at UCLA and member of the AGRE steering committee.
The consortium leveraged the unprecedented statistical power generated by its unique sample set by using "gene chip" technology to look for genetic commonality in autistic individuals culled from almost 1,200 families. 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 neuronal contact and communication, 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 AGP Consortium believes the identification of susceptibility genes will provide profound new insight into the basis of autism offering a route to breakthroughs in diagnosis and new treatments in support of families.