DUX4 and facioscapulohumeral muscular dystrophy: The second FSHD mouse model, the tamoxifen (TMX)-inducible Cre-DUX4 (TIC-DUX4) mouse, has been generated by inserting into the ROSA26 locus of the mouse a single human DUX4 V5-tagged ORF (exon 1) plus its 3′ untranslated region (UTR), followed by the endogenous poly-A sequence (exon 3) and by a second poly-A sequence of the bovine growth hormone gene [136].