NPC1 and neurodevelopmental disorder: Ofseveral neurodevelopmental disorders, primary (congenital) microcephaly andmegalencephaly are the ones caused by impaired or excessive NPC expansion,respectively (Juric-Sekharand Hevner 2019; Mirzaa and others 2004; Pinson and others 2019; Verloes and others1993; Zhang andothers 2020).