The role of KCC2 and NKCC1 in maintaining chloride homeostasis extends beyond brain development, as dysfunctions of these co-transporters are also observed in various neurodegenerative disorders, including Alzheimer’s disease (AD), amyotrophic lateral sclerosis, Parkinson’s disease, and Huntington’s disease [10]. The gene discussed is SLC12A2; the disease is juvenile Huntington disease.