DMD and Becker muscular dystrophy: Restoration of the reading frame in DMD patients would in theory allow the production of a shorter, but partly functional dystrophin protein as seen in less severely affected Becker muscular dystrophy patients.3,4 This can be achieved with antisense oligonucleotides (AONs) that target and induce skipping of specific exons during pre-mRNA splicing.5,6 Exon skipping AONs are thought to act by sterically hindering splicing factors in the recognition of the exon and/or splicing sites.