Three Research Teams Achieve Breakthroughs in Gene Editing for Inherited Epilepsies
Recent research has yielded three separate studies demonstrating the use of advanced gene editing techniques to correct genetic mutations associated with different forms of epilepsy in mouse models. The studies, conducted by research teams at the University of Virginia, The Jackson Laboratory (in collaboration with other institutions), and the University of Zurich, each target mutations in sodium channel genes linked to severe, inherited epilepsies.
University of Virginia: Base Editing for SCN8A Mutation
The intervention was reported to eliminate or significantly reduce seizures, increase overall survival, and improve movement abilities.
Scientists at the University of Virginia School of Medicine employed a technique called base editing to correct a mutation in the SCN8A gene in laboratory mice. SCN8A developmental and epileptic encephalopathy (DEE) is an inherited condition estimated to affect 1 in 56,000 births. The mutation leads to excessive sodium flow into brain neurons, causing hyperexcitability and seizures, which can present in early infancy and include learning disabilities, movement problems, and a risk of sudden unexpected death in epilepsy (SUDEP).
The researchers, led by Dr. Manoj Patel, used base editing to target and correct the single nucleotide mutation. In treated mice, the intervention was reported to eliminate or significantly reduce seizures, increase overall survival, and improve movement abilities. Brain analysis confirmed a reduction in sodium flow and neuronal hyperexcitability. The findings were published in the Journal of Clinical Investigation. The researchers noted the study demonstrates the reversibility of the mutation's impact and provides a potential path for treating SCN8A-related epilepsy, pending further research before human application.
Jackson Laboratory and Collaborators: Base Editing for Dravet Syndrome Mutation
Nearly 60% of the mutated DNA was corrected in treated mice.
A separate study, published in Science Translational Medicine, used adenine base editing (ABE) to correct the R613X mutation in the SCN1A gene in a mouse model of Dravet syndrome. Dravet syndrome is a severe childhood epilepsy caused by mutations in the SCN1A gene, which produces faulty Nav1.1 channels.
According to the study, nearly 60% of the mutated DNA was corrected in treated mice. The treated mice showed fewer seizures and extended survival. The correction restored normal function of Nav1.1 channels and was effective when administered 12 days after birth. The base editor was delivered via a single brain injection in neonatal mice. The study was co-led by Matthew Simon (JAX) and involved collaborations with The Jackson Laboratory, Broad Institute, Children's Hospital of Philadelphia, and UMass Chan Medical School. Researchers stated the work provides proof of concept that a genetic correction approach could be effective for Dravet syndrome.
University of Zurich: Prime Editing for GEFS+ Mutation
After treatment, the frequency of febrile seizures dropped from approximately 80% in the control group to approximately 15% in the treated group.
At the University of Zurich, researchers demonstrated that prime editing could correct a disease-causing mutation in the SCN1A gene directly in the brain cells of a mouse model of genetic epilepsy with febrile seizures plus (GEFS+). Prime editing is a gene editing method that corrects single genomic errors without fully severing the DNA.
The mice carried the same SCN1A mutation found in human GEFS+ patients. After treatment, the mutation was corrected in most nerve cells in a key brain region. The frequency of febrile seizures dropped from approximately 80% in the control group to approximately 15% in the treated group. The treatment also improved nerve cell signaling and increased survival rates. The research team, including postdoctoral researchers Lucas Kissling and Francesca Pietrafesa, stated the method aims to correct the genetic error directly rather than treating the consequences of the mutation.