Concomitantly, agents designed to block myostatin production in adult mouse models [45] confirmed the increase in muscle mass following myostatin inhibition, including in disease models of Becker (BMD) and Duchenne muscular dystrophy (DMD) [31,46,47], dysferlinopathy [48], limb-girdle muscular dystrophy type 2A (LGMD2A) [49], calpainopathy [50], and SMA [29,51,52,53,54]. The gene discussed is SMN1; the disease is Becker muscular dystrophy.