DUX4 and facioscapulohumeral muscular dystrophy: DUX4 target genes were significantly elevated in the 3/8 FSHD muscle biopsy studies profiled by RNA‐seq (Yao et al, 2014; Wang et al, 2019; Wong et al, 2020), while the remaining five studies used microarrays (Bakay et al, 2006; Osborne et al, 2007; Geng et al, 2012; Rahimov et al, 2012; Tasca et al, 2012) (Table 1), potentially highlighting a technical issue.