CRISPR-Induced Deletion with SaCas9 Restores Dystrophin Expression in Dystrophic Models In Vitro and In Vivo.

Duchenne muscular dystrophy (DMD), a severe hereditary disease affecting 1 in 3,500 boys, mainly results from the deletion of exon(s), leading to a reading frameshift of the DMD gene that abrogates dystrophin protein synthesis. Pairs of sgRNAs for the Cas9 of Staphylococcus aureus were meticulously chosen to restore a normal reading frame and also produce a dystrophin protein with normally phased spectrin-like repeats (SLRs), which is not usually obtained by skipping or by deletion of complete exons. This can, however, be obtained in rare instances where the exon and intron borders of the beginning and the end of the complete deletion (patient deletion plus CRISPR-induced deletion) are at similar positions in the SLR.

From gRNA Identification to the Restoration of Dystrophin Expression: A Dystrophin Gene Correction Strategy for Duchenne Muscular Dystrophy Mutations Using the CRISPR-Induced Deletion Method.

The discovery of the CRISPR-Cas9 system raises hope for the treatment of many genetic disorders. We describe here an approach based on the use of a pair of single guide RNAs to form a hybrid exon that does not only restore the dystrophin gene reading frame but also results in the production of a dystrophin protein with an adequate structure of the central rod-domain, with a correct spectrin-like repeat. The therapeutic approach described here involved DMD patient cells having a deletion of exons 51-53 of the DMD gene.

Efficient Restoration of the Dystrophin Gene Reading Frame and Protein Structure in DMD Myoblasts Using the CinDel Method.

The CRISPR/Cas9 system is a great revolution in biology. This technology allows the modification of genes in vitro and in vivo in a wide variety of living organisms. In most Duchenne muscular dystrophy (DMD) patients, expression of dystrophin (DYS) protein is disrupted because exon deletions result in a frame shift.