DUX4 and facioscapulohumeral muscular dystrophy: An inducible mouse model was produced by knocking in a genomic fragment from the D4Z4 repeat belonging to the 4qA allele of a FSHD patient (including the DUX4 ORF, 3′UTR including the DUX4 p(A)) that was placed under the control of a doxycycline-inducible promoter called iDUX4pA [69,70].