SLC18A3 and Neurodevelopmental delay: In the “NDD-genes” group, there were 13 genes (ADADVL, HDAC8, ITPR1, NFIX, OGT, PTPN1, RAB3GAP1, SETD5, SMC3, SLC18A3, SPTBN2, THOC6, and WDR81) without definite reports of seizure-related phenotypes.