Using a combination of NEUROG1, SOX11, ISL1, and LHX3 (NSIL), MNs can be generated from fibroblasts of ALS patients in which the patient-derived MNs manifest various ALS pathologies, including FUS protein mislocalization and neuronal degeneration (Liu et al., 2016). Here, NEUROG1 is linked to amyotrophic lateral sclerosis.