SHANK3 and brain disorder: To understand the detailed neurobiological mechanisms underlying SHANK3-associated brain disorders, more than 10 different Shank3 knock-out (KO) mouse lines carrying deletions of different Shank3 exons (of total 22 exons) have been generated to date, and molecular, cellular, and functional changes in their brains have been characterized (Jiang and Ehlers, 2013; Monteiro and Feng, 2017; Eltokhi et al., 2018).