Asymmetric proteomic development of the pre- and postsynapse was also observed in NGN2 neurons and has been described for iPSC-derived neurons obtained through directed differentiation.83,84 In PB-AD neurons, current responses to GABA puffs remained constant over time, indicating that functional postsynapses already exist at 4 WPI and the expression of GABA receptors remains unaltered at subsequent weeks. This evidence concerns the gene NEUROG2 and Alzheimer disease.