TP53 and microcephaly: Nevertheless, in the case of a p53 hyperactivation in response to DSB formation following irradiation during embryogenesis, p53 can induce massive apoptosis of NPCs and reduced proliferative states in the developing brain culminating in a range of developmental defects including microcephaly (Bowen and Attardi, 2019; Mfossa et al., 2020).