Considering (I) the role of HIF1α in myogenesis and muscle regeneration, (II) the dysregulation of HIF1α in FSHD muscles, and (III) that myogenic differentiation defects are a major characteristic of FSHD muscle cells [23, 26, 30, 31], we hypothesized that an inadequate HIF1α activation could participate in FSHD pathophysiology. The gene discussed is HIF1A; the disease is facioscapulohumeral muscular dystrophy.