DUX4 and facioscapulohumeral muscular dystrophy: However, the Choi et al. early DUX4 target genes were also significantly associated with TIRM status among isogenic FSHD muscle samples (adjusting for age and sex), and the genes comprising the Lymphoblast score were significantly associated with FSHD versus control status as well as TIRM status in isogenic muscle samples (Table 2; Supplementary Table 3).