KCNQ2-Related Benign Infantile Epilepsy in Preterm Dizygotic Twins

Abstract

Potassium voltage-gated channel subfamily Q member 2 (KCNQ2)-related disorders represent a spectrum of overlapping neonatal epileptic phenotypes caused by heterozygous pathogenic variants (PVs) in KCNQ2. The clinical features of KCNQ2-related disorders range from a mild form of benign familial neonatal epilepsy (BFNE) to a severe form with neonatal epileptic encephalopathy. BFNE is an age-dependent familial epilepsy syndrome characterized by a wide spectrum of seizures that begin in otherwise healthy infants between the 2nd and 8th days of life and typically cease spontaneously. A family history of neonatal seizure is crucial for the diagnosis [1]. KCNQ2-related non-familial benign neonatal epilepsy has been previously reported [2]. However, KCNQ2-related benign infantile epilepsy in dizygotic twins with no family history of seizures has not been reported to date. Herein, we report the same PV of the KCNQ2 gene in preterm dizygotic twins who presented with multiple seizures at a corrected age (CA) of 40 weeks. This study was approved by the Institutional Review Board of Daegu Catholic University Medical Center(CR-21-033). The requirement for publication consent was waived because personally identifiable protected health information was not disclosed in this report.Case 1: Dizygotic twins were born by a moth-