DLG4 and psychiatric disorder: Dysfunction of the Dlg family has been implicated in several mental disorders: Dlg4 (also known as PSD95 or SAP90) (Coley and Gao 2018; Funk et al. 2017; Gao and Mack 2021; Grant 2016; Levy et al. 2022; Nagura et al. 2012; Nithianantharajah et al. 2013; Xing et al. 2016), Dlg1 (also known as SAP97) (Gupta et al. 2018; Kay et al. 2022; Uezato et al. 2017), and Dlg2 (also known as PSD93 or Chapsin110) (Winkler et al. 2018; Yoo et al. 2020).