DUX4 and facioscapulohumeral muscular dystrophy: It is likely that these embryonic and non-coding transcripts in the context of muscle cause progressive death of myofibers, as DUX4 expression is toxic in many models of FSHD, including human and murine cell cultures and several animal models (Block et al., 2013; Bosnakovski et al., 2008b; Dandapat et al., 2014; Jagannathan et al., 2016; Jones et al., 2016; Kowaljow et al., 2007; Mitsuhashi et al., 2013; Rickard et al., 2015; Wallace et al., 2011; Wuebbles et al., 2010).