DUX4 and Facioscapulohumeral dystrophy: The articles published by Nunes et al. [29] and Jones et al. [26] have shown that, even in the absence of tamoxifen, the Acta1-MCM;FLExDUX4/+ mouse presents chronic mosaic DUX4 expression, developing a DUX4-induced pathology, which reflects the course of the disease in FSHD patients.