Fig. 1.

Mechanisms of CRISPR-induced exon skipping. a From Li et al. [6], CRISPR/Cas9 induces exon skipping only with the generation of a premature termination codon (PTC) in an exon other than exon 1. b From Gapinske et al. [7], CRISPR-SKIP repurposes the C > T SpCas9 Base editor, composed of the APOBEC1 cytidine deaminase, the SpCas9-D10A nickase, and the PBS1 uracil glycolase inhibitor (UGI), to mutate splice acceptor sites and thus to induce programmable exon skipping. PAM, Protospacer adjacent motif; sgRNA, single guide RNA