When examining the post-stress nuclear relocalisation dynamics of TDP-43 and FUS against an ALS genetic background, we found that VCP mutant ALS MNs recover at the same rate as their control counterparts, suggesting that defects in nuclear import of RBPs are not associated with the early stage of disease recapitulated in iPSC model systems. This evidence concerns the gene TARDBP and amyotrophic lateral sclerosis.