KCNJ10 and cerebellar ataxia: Genetic screens and clinical studies suggest that loss-of-function of KCNJ10 encoding Kir4.1 in humans causes EAST (Epilepsy, Ataxia, Sensorineural deafness, and Tubulopathy) or SeSAME (Seizures, Sensorineural deafness, Ataxia, Mental retardation, and Electrolyte imbalance; Bockenhauer et al., 2009; Scholl et al., 2009; Ohno, 2018).