US20260242782
2026-08-20
Chemistry; metallurgy
C12N15/111
The patent application discusses a CRISPR/Cas-based base editing system designed to treat Duchenne Muscular Dystrophy (DMD) by restoring the function of dystrophin, a crucial protein. DMD is caused by deletions in the dystrophin gene that disrupt its reading frame, leading to muscle degeneration. The base editing system aims to correct these disruptions by altering RNA splice sites, thereby enabling the inclusion or exclusion of specific exons during mRNA processing.
This technology focuses on precise base editing using CRISPR/Cas systems to modify splice sites in genomic DNA. By targeting specific RNA splice sites, the system can induce exon skipping or inclusion, which helps restore the reading frame of the dystrophin gene. This approach contrasts with traditional methods that rely on random indels, offering a more controlled and predictable outcome for gene correction.
The application details various embodiments of the CRISPR/Cas-based base editing system, including its components like guide RNA (gRNA) and fusion proteins. The system can be used to target specific splice sites in the dystrophin gene, such as converting an "AG" splice acceptor to "AA" to promote exon skipping. Additionally, the application covers isolated polynucleotides, vectors, and cells comprising the base editing system, as well as compositions and kits for restoring dystrophin function.
The methodology involves using the CRISPR/Cas-based base editing system to contact cells or subjects with a mutant dystrophin gene. By precisely editing the splice sites, the system facilitates exon skipping or inclusion, thereby restoring the gene's reading frame. This precise editing is achieved without inducing double-stranded DNA breaks, a common issue with traditional CRISPR-Cas9 systems.
The document provides definitions for key terms used throughout the application, such as "comprise," "about," and "AAV" (Adeno-associated virus). It also explains the significance of various biological terms like amino acids, chromatin, and CRISPRs. These definitions ensure clarity and consistency in understanding the technical aspects of the base editing system and its applications.