KCNQ2 and Bilateral tonic-clonic seizure: Further, the loss-of-function human KCNQ2–R213N variant is linked to epileptic encephalopathy in a two-generation pedigree in which various family members exhibited asymmetric quadriplegia, lifelong myokomia, and/or tonic-clonic seizures (Weckhuysen et al., 2012; Miceli et al., 2013; Orhan et al., 2014), further emphasizing the importance of this residue in KCNQ2 gating and in epilepsy.