In a zebrafish model of FSHD, co-injection of both short non-toxic (DUX4-s) and full length (DUX4-fl) of DUX4 protein led to a decrease in the phenotypical abnormalities observed in animals singly injected with DUX4-fl [53]. The gene discussed is DUX4; the disease is facioscapulohumeral muscular dystrophy.