Thursday, November 8, 2012
Scientists have shown that a single protein plays an oversized role in intellectual and behavioral development
The scientists found that mutations in a single gene, which is known to cause intellectual disability and increase the risk of developing autism spectrum disorder, severely disrupts the organization of developing brain circuits during early childhood. This study helps explain how genetic mutations can cause profound cognitive and behavioral problems. The genetic mutations that cause developmental disorders, such as intellectual disability and autism spectrum disorder, commonly affect synapses, the junctions between two nerve cells that are part of the brain's complex electro-chemical signaling system. A substantial percentage of children with severe intellectual and behavioral impairments are believed to harbor single mutations in critical neurodevelopmental genes. Until this study, however, it was unclear precisely how pathogenic genetic mutations and synapse function were related to the failure to develop normal intellect. The study focused on a critical synaptic protein known as SynGAP1. Mutations in the gene that encodes this protein cause disabilities in an estimated one million people worldwide. SynGAP1 is one of the most important genes in cognition - so far, every time a mutation that disrupts the function of SynGAP1 has been found, that individual's brain simply could not develop correctly. It regulates the development of synaptic function like no other gene.