April 7, 2012- Researchers from the U.S. estimate that there are over 1,000 genes that contribute to the risk of autism spectrum disorder, but they say the key may be mutations. A professor of psychiatry and neurology at UCLA, Dr. Daniel Geschwind and his colleagues from Connecticut’s Yale University, the University of Pittsburgh and Carnegie Mellon University completed a whole-exome sequencing on 238 quartets of parent-child.
A quartet is a family of two parents and two children, with one child not having autism spectrum disorder and autism spectrum disorder found in one child. Whole-exome is a strategy of sequencing the coding regions of the selectivity of genome. It is cheaper but still an effective alternative to using whole genome sequencing.
Researchers then compared the rates of mutations between those having autism spectrum disorder and those unaffected by the disorder within the same family. They then compared in the entire study, the mutations in those with autism spectrum disorder.
They discovered a multiple variation among the affected and unaffected groups. In a group of 279 mutations, they were able to identify one instance in children with autism spectrum disorder and not in their siblings, where two mutations that were independent disrupted the SCN2A gene.
Researchers found that same mutation amongst all the children whom were not related but had autism spectrum disorder, therefore confirming its importance in the disorder.