Fig. 1

CRISPR-Cas9 design based on the location of the del45–55-D1 breakpoint. (A) the upper part of the image depicts the genomic architecture along introns 44 and 55 illustrating the relative position of the promoter of the Dp140 and Dp116 dystrophin isoforms, as well as the location of the lncRNA 44s, 44s2, 55s and 55as. The figure below depicts the specific breakpoints in introns 44 and 55 of the D1 deletion group (del45–55-D1), illustrating their impact on the aforementioned elements (dotted lines indicate the deleted region). (B) the genomic sequences of introns 44 and 55 are illustrated, with the location of the patient breakpoints indicated by black arrowheads. The gRNAs targeting each intron are represented by blue letters, and their PAM (protospacer adjacent motif) sequences are indicated in red. Purple arrowheads indicate the location of the expected Cas9 DSB (double-strand break). (C) genomic sequences of the deletion junctions, confirmed by Sanger sequencing of (1) the patient harbouring this specific deletion and (2) the Edited∆45–55 clone