The p53 activation is described as a major mechanism implicated in EJC-induced microcephaly, as it rescues the brain size phenotype in all Eif4a3, Magoh and Rbm8a mutants when it is inactive (Mao et al., 2016; Bowen and Attardi, 2019; Chuang et al., 2019). This evidence concerns the gene EIF4A3 and microcephaly.