SLC12A2 and Down syndrome: The upregulation of NKCC1 and the subsequent shift of GABAA to excitatory functions is a fundamental transformation shown in some nervous diseases, such as autism, temporal lobe epilepsy (Ben-Ari et al., 2012; Gharaylou et al., 2019a), schizophrenia (Kehrer et al., 2008), neuropathic pain (Côté, 2020), and animal models of the Down syndrome (Potier et al., 2014).