DMD and Duchenne muscular dystrophy: Ivanova and colleagues demonstrated that CPPs conjugated to a 20-mer PNA for targeting dystrophin correction in exon 23 in the DMD mouse model (mdx) showed higher exon skipping activity in differentiated mdx mouse myotubes and higher number of dystrophin-positive fibres when injected in the tibilias anterior of mdx mice compared to naked PNA [53].