KCNQ2 and paroxysmal nocturnal hemoglobinuria: The human gene KCNQ2encodes the Kv7.2 subunit of voltage-gated K+ channels,35,36 and its mutations are associated with neurological disorders innewborns characterized by a wide phenotypic heterogeneity,37 including benign familial neonatal seizures(BFNS) and peripheral nerve hyperexcitability (PNH).38 In particular, studies on a patient affected by PNH39 have identified a Kv7.2 mutation correspondingto the loss of the R207 arginine in S4 (R207Q).