Early Childhood Brain Development Linked to Development of Epilepsy

August 31, 2009

Researchers have discovered what they call “the first genetic link” between a form of partial epilepsy and the development of the brain during early childhood, particularly between the ages of one and five.

Researchers from Beth Israel Deaconess Medical Center have discovered what they call “the first genetic link” between a form of partial epilepsy and the development of the brain during early childhood, particularly between the ages of one and five.

Senior author Matthew Anderson, MD, PhD, a principal investigator in the departments of neurology and pathology at Beth Israel and assistant professor of Neurology and Pathology at Harvard Medical School, and his team of researchers used a genetically engineered mouse model and brain slice patch-clamp electrophysiology techniques for their research, finding that a mutant form of the Leucine-rich glioma-inactivated 1 (LGI1) gene prevents normal brain development.

According to Anderson, the “first clue” to the gene’s impact on brain development was the team’s discovery that “LGI1 is not expressed until the exact time when excitatory synapses are matured.” The team then discovered, according to Anderson, that the mutated form of the LGI1 gene was “prohibiting excitatory synapses from being adequately pruned, leading to an increased excitability of circuits in the brain which left it prone to excessive synchronous discharges that are characteristic of epilepsy.”

The researchers explained that inadequate “pruning” of excess synapses can cause excess growth, which then leads to “to excessive transmission of excitatory signals and the development of pathological conditions, including learning disabilities and autism in addition to epilepsy.”

Anderson explained that this discovery of a genetic component to seizures may one day enable physicians to more effectively treat epilepsy.

“One important reason to identify genetic causes of epilepsy is the hope that these discoveries will eventually lead to new therapies,” Anderson continued. “By identifying this pathway, we may have found a new target for future drug development.”

Results of the study were also published in the Advance On-line issue of Nature Medicine.