July 11, 2013
Full Genome Sequencing Of Autistic Patients Reveals Groundbreaking Insights
Rebekah Eliason for redOrbit.com - Your Universe Online
New full genome sequencing performed on individuals with autism spectrum disorder (ASD) and their family members has provided a complete inspection of the vast genetic variations associated with ASD. This study was a collaborative effort formed by the world's leading ASD advocacy group Autism Speaks.Included in the results were both spontaneous and inherited genetic variations that were found in one half of the families sequenced. Participants of the study included 32 unrelated Canadian individuals with ASD along with their families.
This groundbreaking discovery of genetic variations in 50 percent of individuals with clinical manifestations of ASD or accompanying symptoms is particularly significant because up to this point diagnostic technology has only been able to determine a genetic basis for ASD in about 20 percent of the individuals tested. The large increase in individuals identified with genetic variations is due to the ability to perform comprehensive and consistent genome sequencing.
Autism Speaks Chief Science Officer and study co-author Robert Ring, PhD said that, "From diagnosis to treatment to prevention, whole genome sequencing efforts like these hold the potential to fundamentally transform the future of medical care for people with autism."
In this study, genetic variations associated with risk for ASD, including spontaneous and other inherited DNA lesions, were discovered in four genes not previously recognized for ASD, nine genes previously associated with ASD risk and eight genes that are candidates for ASD risk. A combination of the genes was found in some families. Additionally, risk alterations were discovered in genes for conditions such as social-cognitive deficits, epilepsy and ASD-associated CHARGE syndrome.
Lead author Dr. Stephen Scherer explained, "Whole genome sequencing offers the ultimate tool to advance the understanding of the genetic architecture of autism. In the future, results from whole genome sequencing could highlight potential molecular targets for pharmacological intervention, and pave the way for individualized therapy in autism. It will also allow for earlier diagnosis of some forms of autism, particularly among siblings of children with autism where recurrence is approximately 18 per cent."
Autism Speaks Vice President for Scientific Affairs Andy Shih, PhD, who oversees the collaboration founded by Autism Speaks, announced in 2011 that, "As we continue to test more individuals and their family members from the AGRE cohort, we expect to discover and study additional genetic variants associated with autism. This collaboration will accelerate basic and translational research in autism and related developmental disabilities and this collection of sequenced genomes will facilitate new collaborations engaging researchers around the world, and enable public and private entities to pursue pivotal research."
In this beginning study, the 32 individuals with ASD along with their two parents and three members of one control family were tested for a total of 99 individuals participating. Researchers plan further studiesÂ to collect whole genome sequences from more than 2,000 families with two or more children on the autism spectrum taken from the Autism Speaks AGRE collection.
The collaboration included researchers from Autism Speaks, Duke University School of Medicine, The Hospital for Sick Children of Toronto, BGI and other institutes. This study was published in American Journal of Human Genetics.