Mustafa Bilal Bayazit

1 Introduction Facioscapulohumeral muscular dystrophy (FSHD) is the third most common muscular dystrophy affecting approximately 1 in 8333 individuals worldwide [1-3]. It is characterized by progressive skeletal muscle weakness and wasting, particularly in the face, shoulders, upper arms, and lower extremities. FSHD is an autosomal dominant or digenic disorder caused by the de-repression of the transcription factor DUX4 in skeletal muscle.