Theoretical applicability of exons 45–55 skipping to patients with out-of- and in-frame deletions. 3232 and 1611 patients with out-of-frame and in-frame deletions, respectively, were extracted from the Leiden DMD database (as of 22 June 2018). The applicability to out-of- (red) and in-frame deletions (blue) was examined. As single exon skipping has not been fully correlated with functional correction, the applicability only to out-of-frame deletions is shown. In contrast, the applicability of exons 45–55 skipping thought to enable the production of functionally improved dystrophin, is shown for both frame types.