Gene mutation behind brain defects identified
Mutations in a single gene - that causes intellectual disability and increases the risk of developing autism spectrum disorder - severely disrupts the organization of developing brain circuits during early childhood, a new study has revealed.
This study by scientists from the Florida campus of The Scripps Research Institute helps explain how genetic mutations can cause profound cognitive and behavioural problems.
"In this study, we did something no one else had done before," Gavin Rumbaugh, a TSRI associate professor who led the new research, said.
"Using an animal model, we looked at a mutation known to cause intellectual disability and showed for the first time a causative link between abnormal synapse maturation during brain development and life-long cognitive disruptions commonly seen in adults with a neurodevelopmental disorder," he said.
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, according to the paper.
"You might think this accelerated development of brain circuits would make you smarter," Rumbaugh said.
"But the increased excitability actually disorganizes brain development. We think that early maturation of these excitatory synapses disrupts the timing of later developmental milestones. It rains down chaos on this complex process, preventing normal intellectual and behavioural development," he said.
The study has been published in the journal Cell.