,7,8,9 Recently, Chai et al. found that bi-allelic variants in PPIL1 (MIM: 601301) and PRP17 (MIM: 605585) cause similar neurodegenerative disorders, where affected individuals have microcephaly and pontocerebellar hypoplasia (MIM: 619301 and 619302).10 Here, CDC40 is linked to microcephaly.