SNX27 and Down syndrome: A case in point is sorting nexin-27 (SNX27), in which destabilised expression is associated with Down’s Syndrome and coding mutations are observed in patients with pleomorphic phenotypes that have at their core epilepsy, developmental delay and subcortical white matter abnormalities (Damseh et al., 2015; Parente et al., 2020; Wang et al., 2013).