Compared to the mutations of its binding partner Munc18-1, which results in DEEs with an early onset epilepsy (Ohtahara syndrome or West syndrome), missense mutations in Stx1b cause DEE which presents with a later onset epileptic disorder (Saitsu et al., 2008; Wolking et al., 2019; Krenn et al., 2021). This evidence concerns the gene STXBP1 and early-infantile DEE.