KCNA2 and infantile epileptic encephalopathy: It has been reported that de novo KCNA1 variants (Pro403Ser; Val404Ile; Pro405Leu) in the PVP motif in the 6th transmembrane domain (S6) abolish channel function and cause infantile epileptic encephalopathy and cognitive impairment similar to recurrent KCNA2 variants (Rogers et al., 2018).