GAMT and glycine encephalopathy: The top downregulated enriched genes in this pathway are key players of neurodevelopment, since biallelic variants of GLDC, GAMT, and ALDH7A1 are respectively associated with glycine encephalopathy (GCE; MIM #605899), cerebral creatine deficiency syndrome 2 (CCDS2; MIM #612736) and pyridoxine-dependent epilepsy (EPD; MIM #266100).