Work

Single-AAV Delivery of the SpCas9 Nickase Improves CAG/CTG Repeat Contraction in a Mouse Model of Huntington’s Disease

Year: 2026

Type: preprint

Abstract: The best studied Cas9 enzyme, from Streptococcus pyogenes , is thought to be too large to be efficiently packaged into a single adeno-associated virus (AAV) together with a single-guide (sg) RNA cassette, requiring a dual-vector system. Here we have circumvented this limitation and packaged the full CRISPR system into a single AAV by using a single promoter driving the expression of both the Cas9 enzyme and a sgRNA. We compared the ability of the dual and single vector systems to induce contraction of CAG/CTG repeats in the striatum of a Huntington’s disease model. We show that the all-in-one system led to larger contractions of the CAG/CTG repeats. This approach provides a more efficient and less costly approach for in vivo gene editing and improves the translational potential of AAV-mediated delivery of Cas9. One sentence summary Delivery of CRISPR-Cas9 nickase in a single AAV improves contraction of CAG repeats in HD.

Source: bioRxiv (Cold Spring Harbor Laboratory)

DOI: 10.64898/2026.10.30.762787

Authors: Alvaro Murillo, Alys N. Aston, Mariah J. Lelos, Vincent Dion

Institutions: UK Dementia Research Institute, Cardiff University

Language: English

Topic: Virus-based gene therapy research

Subfield: Genetics

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

SDG: Good health and well-being

Open Access status: green

Funders: Cardiff University, UK Dementia Research Institute, Medical Research Council