For example, Israel and colleagues were one of the first to show that iPSC-derived neurons obtained from reprogrammed fibroblasts from AD patients with both the sporadic and familial form of the disease, were able to replicate some of the disease hallmarks including significantly higher levels of phospho-tau (Thr231), as well as Aβ(1/40) and active glycogen synthase kinase-3β (aGSK-3β) [131]. The gene discussed is MAPT; the disease is Alzheimer disease.