Exceptions to the requirement for array contraction for generation of detectable DUX4-fl transcript were seen in normal testis and in myoblasts and myotubes from patients with a variant of FSHD called FSHD2, which is associated with inappropriate expression of DUX4-fl RNA from 4q35 despite a lack of contraction of the D4Z4 array [8]. Here, DUX4 is linked to facioscapulohumeral muscular dystrophy.