Examining each gene in the p53 pathway according to its p53 weighting in PROGENy revealed that the genes with the strongest responsiveness in p53 activity in ALS iPSMNs included CDKN1A, SESN1, RRM2B, MDM2, C2orf66, ZNF561 and ZMAT3 (Fig. 2e). Here, ZMAT3 is linked to amyotrophic lateral sclerosis.