PHF6 and cask-related x-linked intellectual disability: A number of XLID genes appear to impair neurogenesis via altering NSC fate (Bustos et al, 2018; Kim et al, 2016; Luo et al, 2010; May et al, 2015; Selvan et al, 2018; Telias et al, 2015), raising the question of whether Phf6 mutations impact the NSC pool in the developing brain.