Journal of Pediatric Epilepsy 2024; 13(01): 006-010
DOI: 10.1055/s-0043-1770794
Case Report

Self-limited Familial Neonatal Epilepsy due to the c.1589G > A Novel Pathogenic Variant in KCNQ2: A Family Report

1   Department of Pediatric Neurology, Tepecik Training and Research Hospital, University of Health Sciences, Izmir, Turkey
Ozge Ozer Kaya
2   Department of Medical Genetics, Tepecik Training and Research Hospital, Genetic Diagnosis Center, University of Health Sciences, Izmir, Turkey
Fatma Kusgoz
1   Department of Pediatric Neurology, Tepecik Training and Research Hospital, University of Health Sciences, Izmir, Turkey
Nihal Olgac Dundar
3   Department of Pediatric Neurology, Faculty of Medicine, Izmir Katip Celebi University, Izmir, Turkey
3   Department of Pediatric Neurology, Faculty of Medicine, Izmir Katip Celebi University, Izmir, Turkey
› Institutsangaben


Self-limited familial neonatal epilepsy is an autosomal dominant epileptic syndrome characterized by episodes of seizures occurring in the first days of life. Most patients have heterozygous mutations of KCNQ2 gene located on 20q13. A variety of clinical phenotypes have been associated with KCNQ2 mutations, making the prediction of this rare entity difficult. Herein, we report a rare KCNQ2 variant in two siblings with self-limited familial neonatal epilepsy. The siblings had tonic seizures accompanied by clonic jerks in the first few days after birth. Genetic analysis of the siblings revealed a heterozygous KCNQ2 variant: c.1589G > A; (p.Ser530Asn). The identical variant subsequently was identified in the mother. To our knowledge, this variant has not been previously reported in individuals with KCNQ2-related disease. This is the first report that reveals c.1589G > A variant of KCNQ2 gene as a pathogenic variant in two siblings.

Ethics Declarations and Consent

Local institution ethics committee approval was obtained for this brief case report. Written informed consent was obtained from siblings' parents following a detailed explanation.


Eingereicht: 23. März 2023

Angenommen: 28. Mai 2023

Artikel online veröffentlicht:
28. Juli 2023

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