SLC12A5 and mood disorder: Significant KCC2-focused clinical and preclinical research efforts by clinicians and scientists over the past decade have implicated neuronal KCC2 hypofunction as a conserved pathology in epilepsies, chronic pain, neurodevelopmental, neurotraumatic, neurodegenerative, age-related, and psychiatric/mood disorders (Kaila et al., 2014; Duy et al., 2020; Tang, 2020; Belperio et al., 2022; Hegarty and Stanicka, 2022; Liedtke, 2022; Keramidis et al., 2023; Khademullah et al., 2023; Lam et al., 2023; Mcmoneagle et al., 2023; Pressey et al., 2023; Tomita et al., 2023; Mcardle et al., 2024).