Western blot analysis of the exon 48–50 deleted cells. No dystrophin could be observed in non-treated (NT) or treated myotubes. Each treatment was performed in duplo. Myosin staining was used as a loading control and to confirm that myogenicity was sufficient to allow dystrophin expression (data not shown). Different dilutions of protein from control cells were used as a positive control (right panel). Levels of 1% of the normal levels were detectable.