By: Clare Logan
What is the SCN8A Gene?
The SCN8A gene is essential for the proper transmission of electrical signals in both the brain and the body’s nervous system. The SCN8A gene aids in the production of a protein that assists in regulating the flow of sodium ions into nerve cells, which is crucial for generating electrical impulses. These impulses are how nerve cells communicate with each other, enabling the brain to control movements, sensations, and various other functions throughout the body. Without proper functioning of this gene, the electrical signals in the nervous system can become disrupted, leading to various neurological disorders, most notably SCN8A-related epilepsy. Variants, also known as mutations, in the SCN8A gene often cause disorders that onset in early childhood.
SCN8A-Related Epilepsy
SCN8A-related epilepsy is a rare and acute genetic condition marked by early developmental delays, intellectual disability, and frequent, hard-to-control seizures. Other observable conditions common in those with SCN8A-related epilepsy are movement disorders, autism spectrum disorder, gastrointestinal disorders, and visual impairments. The majority of the documented variants in the SCN8A gene are de novo, meaning they occur for the first time in the affected individual rather than being inherited from the parents. These changes are gain-of-function mutations, which means the variant causes the gene to produce a protein that is overly active or functioning abnormally. This overactivation can cause the nerve cells to also become overactive, sending too many or too frequent signals, which interferes with normal brain and body function. SCN8A-related epilepsy looks very different from person to person, and the severity can vary greatly. These variations in how the condition manifests make it difficult to fully understand and predict the course of the disease for each person.
Research and Treatment
There is limited research on the treatment experience of individuals with SCN8A-related epilepsy, but we commonly see that severe forms of this epilepsy are incredibly drug-resistant, meaning the medications have limited or unpredictable effects. In some cases, anti-seizure medications (ASM’s) can even exacerbate one’s seizures. Since SCN8A-related epilepsy is a relatively new disorder, given the first SCN8A human variant was noted in 2012, there is a common dissatisfaction with current therapies, as they often fail to effectively control seizures. Currently, there is no standard treatment protocol for this patient group. This highlights a significant gap in the availability of safe and effective treatment options, as improved seizure control could greatly enhance the quality of life for both patients and their caregivers.
If you or a loved one suffers from SCN8A-related epilepsy, you are not alone, and we can endeavor to address currently unmet needs by promoting ongoing collaboration between families and their healthcare providers, as well as by increasing awareness and understanding of this rare and acute disease.
Resources:
Hammer, Michael F., and Dinesh Talwar. “What Is SCN8A?” Edited by Beth Sheidley, The Epilepsy Foundation, The Epilepsy Foundation, www.epilepsy.com/sites/default/files/2023-03/SCN8A_March2023.pdf. Accessed 4 Mar. 2025.
“Epilepsy and Seizures.” National Institute of Neurological Disorders and Stroke, U.S. Department of Health and Human Services, www.ninds.nih.gov/health-information/disorders/epilepsy-and-seizures. Accessed 4 Mar. 2025.
Alison Cutts, Hillary Savoie, Michael F. Hammer, John Schreiber, Celene Grayson, Constanza Luzon, Noam Butterfield, Simon N. Pimstone, Ernesto Aycardi, Cynthia Harden, Chuck Yonan, Eric Jen, Trung Nguyen, Tara Carmack, Dietrich Haubenberger, Clinical characteristics and treatment experience of individuals with SCN8A developmental and epileptic encephalopathy (SCN8A-DEE): Findings from an online caregiver survey, Seizure,Volume 97, 2022, Pages 50-57 ISSN 1059-1311, https://doi.org/10.1016/j.seizure.2022.03.008.
