SCN8A Gene Mutation Role In Epilepsy Unveils Clues To Better Seizure Therapies


In the latest concluded American Epilepsy Society’s (AES) 69th Annual Meeting, three studies highlight how the mutation in SCN8A gene, which is widely known as the underlying cause of early infantile epileptic encephalopathy (EIEE) and other neurological problems, affect the brain and its functions.

Early infantile epileptic encephalopathy (EIEE) is a heterogeneous group of epilepsy syndromes associated with severe cognitive and behavioral disturbances. It includes a wide array of epileptic conditions which include Dravet syndrome, Ohtahara syndrome, West syndrome, Lennox-Gastaut syndrome, myoclonic-astatic epilepsy, and Landau-Kleffner syndrome.

These syndromes are debilitating, devastating and potentially-fatal. Thus, studies are geared towards finding its etiology or cause, and developing effective seizure therapies and diagnostic strategies to prevent severe complications to arise.

The SCN8A gene affects the function of brain cells and mutations on this gene can cause various neurological conditions like epilepsy and learning problems. In 2010, the role of SCN8A gene wasidentified as a precursor of EIEE and since then, technological advances in genetic testing helped a lot of patients to receive appropriate treatment options. In fact, it is now known that SCN8A mutations can cause around 1 percent of all epileptic seizures.

The first study was conducted by researchers at the University of Michigan and it shows that defective electrical signaling in the brain may cause seizures in patients diagnosed with EIEE. One mutation called missense mutation p.Asn1768Asp (N1768D) was found to affect sodium currents similar to that of electric signals in the hippocampus.

In the second study, scientists from the Danish Epilepsy Centre, University of Leipzig and Schön Klinik Vogtareuth and the University of Tübingen analyzed gene sequences of SCN8A in 35 patients diagnosed with epilepsy. The findings show that the scope of SCN8A-related epileptic conditions includes those from familial and periodic cases.

In the third study, scientists from the University of Michigan identified new therapies that can be used for patients with EIEE. They analyzed samples of cells from patients diagnosed with epilepsy to determine the process on how SCN8A mutations influence the electro-physiology of the brain. When these mutations occur, it may cause EIEE that may lead to severe epilepsy and eventually, cognitive impairment. Sometimes, these patients are at a greater risk of sudden unexpected death in epilepsy (SUDEP).

“These strategies can be used in future studies as a novel platform for identifying effective drug therapies to ameliorate seizures,” Dr. Andrew Tidball, a postdoctoral fellow at the University of Michigan said in a press release.