Med23 CKO mice display an impaired performance in the spatial memory, which is consistent with the known functions of adult hippocampal neurogenesis (Ming and Song, 2011; Zhang et al., 2013, 2014), and may be one of factors contributing to the intellectual disability associated with the missense mutation of Med23 (Hashimoto et al., 2011; Trehan et al., 2015). Here, MED23 is linked to Intellectual disability.