New research from the Howard Florey Institute in Melbourne has shown why mutation in a single gene can cause epilepsy in infants.
Infants are more susceptible to seizures because their brains are developing at a rapid rate, making their brain cells ‘excitable'. Their neurons are growing and making new connections with other nerve cells, which can disrupt normal brain activity and results in epilepsy.
Infants have protective mechanisms in their brains to control this excitability, but now the Florey scientists have uncovered that a single gene mutation prevents a specific ion channel from functioning correctly, thus causing excitability which results in epilepsy.
Dr Steven Petrou and his team knew the genetic mutation existed, but did not know its impact on brain function or that it may control excitability in infants' brains.
“This discovery is helping us to understand how and why this form of epilepsy, known as benign familial neonatal-infantile seizures, appears in these infants,” Dr Petrou said.
“Interestingly, we also found that the ion channel which carries the mutation is itself naturally protective as it limits excitability in the infant brain by waiting to fully ‘switch on' only in the adult brain.
“The mutation accelerates this normally delayed development change, leaving the susceptible infant brain with an overly excitable channel and epilepsy.
“If this switch to a more excitable state occurs too early during brain development, it is possible that epilepsy and other neurological disorders develop.