NLGN4X and autism: The extensive investigation of the contribution of the neuroligin (NLGN)/neurexin (NRXN) family of cell adhesion molecule and SRC Homology 3 Domain (SH3) and multiple ankyrin repeat domains (SHANK) family of glutamatergic postsynaptic density protein and their autism-associated mutations (Jiang and Ehlers, 2013; Trobiani et al., 2020), which cumulate into the excitation-inhibition balance model of autism development (Sohal and Rubenstein, 2019).