Abnormal dendritic spine density and altered AMPAR internalization have been suggested in epilepsy (Isokawa et al, 1997), schizophrenia (Glantz & Lewis, 2000), and autism spectrum disorder (Hutsler & Zhang, 2010), as well as in disease models of fragile X (Fmr1-knockout) (Jawaid et al, 2018) and Rett syndrome (Mecp2-mutant) (Chao et al, 2007), highlighting the importance of HSD regulation for neuronal homeostasis. Here, CHST3 is linked to epilepsy.