This is not surprising as several of the key primary microcephaly genes (CDK5RAP2, ASPM, WDR62, and MCPH1) (Jackson et al., 2002; Bond et al., 2005; Shen et al., 2005; Yu et al., 2010) are essential for the control of mitosis and cell cycle progression (Cox et al., 2006; Jean et al., 2020). Here, MCPH1 is linked to microcephaly.