CRISPR activation for SCN2A-related neurodevelopmental disorders.
Publication Year:
2025
PubMed ID:
40963013
Funding Grants:
Public Summary:
The majority of neurodevelopmental disorders (NDDs) single gene diagnoses act via haploinsufficiency, where only one of the two gene copies is functional1. SCN2A haploinsufficiency is one of the most frequent causes of NDD, often presenting with autism spectrum disorder (ASD), intellectual disability (ID), and, in a subset of children, refractory epilepsy2. Here, using SCN2A haploinsufficiency as a proof-of-concept, we show that upregulation of the existing functional gene copy via CRISPR activation (CRISPRa) can rescue neurological-associated phenotypes in Scn2a haploinsufficient mice. We first show that restoring Scn2a expression in adolescent heterozygous Scn2a conditional knock-in mice rescues electrophysiological deficits associated with Scn2a haploinsufficiency (Scn2a+/−). Next, using an adeno-associated virus (AAV) CRISPRa-based treatment in adolescent mice, we show that we can correct intrinsic and synaptic deficits in neocortical pyramidal cells, a major cell type that contributes to NDDs and seizure etiology in SCN2A haploinsufficiency. Furthermore, we find that systemic delivery of CRISPRa protects Scn2a+/− mice against chemoconvulsant-induced seizures. Finally, we also show that AAV-CRISPRa treatment rescues excitability in SCN2A haploinsufficient human stem-cell-derived neurons. Our results showcase the potential of this therapeutic approach to rescue SCN2A haploinsufficiency and demonstrates that rescue even at adolescent stages can ameliorate neurodevelopmental phenotypes.
Scientific Abstract:
Most neurodevelopmental disorders with single gene diagnoses act via haploinsufficiency, in which only one of the two gene copies is functional(1). SCN2A haploinsufficiency is one of the most frequent causes of neurodevelopmental disorder, often presenting with autism spectrum disorder, intellectual disability and, in a subset of children, refractory epilepsy(2). Here, using SCN2A haploinsufficiency as a proof-of-concept, we show that upregulation of the existing functional gene copy through CRISPR activation (CRISPRa) can rescue neurological-associated phenotypes in Scn2a haploinsufficient mice. We first show that restoring Scn2a expression in adolescent heterozygous Scn2a conditional knock-in mice rescues electrophysiological deficits associated with Scn2a haploinsufficiency (Scn2a(+/-)). Next, using an adeno-associated virus CRISPRa-based treatment in adolescent mice, we show that we can correct intrinsic and synaptic deficits in neocortical pyramidal cells, a major cell type that contributes to neurodevelopmental disorders and seizure aetiology in SCN2A haploinsufficiency. Furthermore, we find that systemic delivery of CRISPRa protects Scn2a(+/-) mice against chemoconvulsant-induced seizures. Finally, we also show that adeno-associated virus CRISPRa treatment rescues excitability in SCN2A haploinsufficient human stem-cell-derived neurons. Our results showcase the potential of this therapeutic approach to rescue SCN2A haploinsufficiency and demonstrates that rescue even at adolescent stages can ameliorate neurodevelopmental phenotypes.
