Muscular dystrophies are a generic name for a group of inherited muscle diseases that cause degeneration of skeletal muscles. Patients with a muscular dystrophy experience progressive muscle weakness over time, and may eventually become wheelchair dependent. In this thesis, I focussed on two forms of muscular dystrophy, myotonic dystrophy type 1 (DM1) and facioscapulohumeral muscular dystrophy (FSHD). For both diseases, progress towards new treatments is ongoing, but has not yet been able to provide a curative therapy.