SLC12A5 and atypical Rett syndrome: Given the great importance of both GABAARs and KCC2 in maintaining the E/I balance, several neurological and psychiatric disorders are associated with their deficiency, resulting in hyperexcitability of neuronal networks, such as epilepsy, neuropathic pain, posttraumatic spasticity, Huntington disease, schizophrenia and Rett syndrome 33-37.