Single-dose genome editing therapy rescues auditory and vestibular functions in adult mice with DFNA41 deafness

Genome editing has the potential to treat genetic hearing loss. However, current editing therapies for genetic hearing loss have shown efficacy only in hearing rescue. In this study, we evaluated a rescue strategy using adeno-associated virus (AAV) type 2-mediated delivery of Staphylococcus aureus Cas9-sgRNA in the mature inner ear of the P2rx2V61L/+ mouse model of autosomal dominant deafness-41 (DFNA41), a dominant, delayed-onset, and progressive hearing loss in humans. We demonstrate that local injection in adult mice results in efficient and specific editing that abolishes the mutation without notable off-target effects or AAV genome integration. Editing effectively restores long-term auditory and vestibular function. Editing further protects P2rx2V61L/+ mice from hypersensitivity to noise-induced hearing loss, a phenotype also observed in patients with DFNA41. Intervention in mice at a juvenile stage broadens the frequency range rescued, highlighting the importance of early intervention. An effective and specific gRNA for the human P2RX2 V60L mutation has been identified. Our study establishes the feasibility of editing to treat DFNA41 caused by P2RX2 V60L mutation in humans and opens an avenue for using editing to rescue hearing and vestibular function while mitigating noise-induced hearing loss.