Interestingly, inactivating mutations in PLK4, STIL, CPAP (also known as CENPJ), or SAS6 can lead to autosomal recessive primary microcephaly (MCPH) in humans [35], while their overexpression can induce centriole amplification, centriole elongation, and/or centrosome aberrations usually accompanied by structural and/or numerical abnormalities [20, 22]. Here, PLK4 is linked to autosomal recessive primary microcephaly.