A landmark study published in Cell has shown that prime editing, a cutting-edge form of gene editing, can correct mutations causing Alternating Hemiplegia of Childhood (AHC) with a single in-brain injection. The research team fixed the most prevalent ATP1A3 gene mutations in mouse models, reducing symptoms and more than doubling survival, a first-of-its-kind success in treating a neurological disease directly in the brain. CRISPR-based gene editing was delivered through an harmless adeno-associated virus called AAV9. In parallel, patient-derived cells (iPSCs) responded similarly, reinforcing the method’s promise for human translation. Importantly, this success opens the door to targeting other genetic brain disorders previously deemed untreatable. Although results are preliminary, this study provides robust proof‑of‑concept for personalized gene editing in the brain and opens doors toward potential treatments for other intractable genetic neurological disorders.
When a neuron is damaged, segments of RNA produce proteins that help repair the lesion. However, in neurological disorders such as ALS and spinal muscular atrophy, or following damage to the spinal cord, the mechanisms for transporting life-sustaining RNA to damaged sites in the cell fail. As a result, RNA molecules are unable to reach their target, and damage becomes permanent. Stanford researchers have developed a technology dubbed CRISPR-TO, to transport RNA to specific areas of a neuron, where it can repair and even regenerate parts of the cell. The researchers used a version of CRISPR, called CRISPR-Cas13, to target individual RNA fragments. The researchers associated Cas13 with specific localization signals that act as addresses, telling Cas13 where to deliver the RNA. Each location in the cell has its own address molecule, so the researchers can direct RNA to different locations by adding different molecules to the cell. Their work, supported by the National Institutes of Health, forms the basis of a new class of therapies which the researchers call “RNA space medicine”, and which they hope will pave the way for the treatment of neurological diseases and trauma.