FOXO1 and myopathy: Whilst FOXO1 inhibition enhanced the myogenic program in both ALS and VCP-myopathy myoblasts (Supplementary Fig. 11f), particularly in VCP-myopathy with a 2.75-fold increase in the differentiation index, we did not observe mislocalization of FOXO1 to the nucleus (Supplementary Fig. 11c) or a negative impact on myogenesis (Supplementary Fig. 11d, e).