ArticleAnnals of neurology2012
KCNQ2 encephalopathy: emerging phenotype of a neonatal epileptic encephalopathy.
Article in Annals of neurology, 2012. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 230 papers, 3 of them syntheses that pooled it.
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Who cites it
230 citing papers in PubMed, 3 syntheses or guidelines pooled it, 503 citations in OpenAlex.
- Genetic Neonatal-Onset Epilepsies and Developmental/Epileptic Encephalopathies with Movement Disorders: A Systematic Review.International journal of molecular sciences · 2021Pooled it
- Intellectual Disability and Potassium Channelopathies: A Systematic Review.Frontiers in genetics · 2020Pooled it
- Genetic regulation of gene expression in the epileptic human hippocampus.Human molecular genetics · 2017Pooled it
- Precision Medicine in Epilepsy: Diagnostic Yield by Next-Generation Sequencing and Genotype-Phenotype Findings in a Romanian Cohort.International journal of molecular sciences · 2026Article
- Biochemical and Immunohistochemical Associations of TDP-43 and Cryptic RNA With Hippocampal and Amygdala Volumetrics in Alzheimer's Disease.Annals of neurology · 2026Article
- Neonatal Epilepsy: Beyond Seizures in a Developing Brain-A Narrative Review.Brain sciences · 2026Review
- Article
- KCNQ2 neonatal epilepsy: Impact of prompt diagnosis and treatment, and early predictors of outcome severity.Epilepsia open · 2026Article
- Epilepsy: Molecular Pathogenesis and Emerging Therapies.MedComm · 2026Review
- Novel proteolytic post-translational modification in voltage-gated potassium channel KCNQ2.Scientific reports · 2026Article
- Kcnq2 R213 knock-in mice reveal variant- and region-specific mechanisms underlying self-limited familial neonatal-infantile epilepsy and early infantile developmental and epileptic encephalopathy.Acta neuropathologica communications · 2026Article
- Neurodevelopmental features in KCNQ2 developmental and epileptic encephalopathy may have limited associations with KEpilepsia open · 2026Article
- Mislocalization of KCNQ2 Channels as a Pathogenic Mechanism in KCNQ2 Developmental and Epileptic Encephalopathy.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2026Article
- Navigating the complexities of dual CNV findings: a case of DEE7 caused by aFrontiers in pediatrics · 2026Article
- Biophysical and structural mechanisms of epilepsy-associated mutations in the S4-S5 Linker of KCNQ2 channels.Channels (Austin, Tex.) · 2025Article
- Mapping the knowledge of epilepsy and Potassium Channels: A scientometric analysis in CiteSpace and VOSviewer.IBRO neuroscience reports · 2025Article
- Imaging brain development in a KCNQ2-developmental and epileptic encephalopathy mouse model: identifying early biomarkers for functional and structural brain changes.EBioMedicine · 2025Article
- Pharmacological Actions of Potassium Channel Openers on Voltage-Gated Potassium Channels.Pharmaceuticals (Basel, Switzerland) · 2025Article
- Persistent Na+ current couples spreading depolarization to seizures in Scn8a gain-of-function mice.Brain : a journal of neurology · 2025Article
- Cryptic splicing in synaptic and membrane excitability genes links TDP-43 loss to neuronal dysfunction.bioRxiv : the preprint server for biology · 2025Article
170 more citing papers are in PubMed but not listed here.
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Authors and funding
23 authors at 12 institutions in 5 countries.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveKCNQ2 and KCNQ3 mutations are known to be responsible for benign familial neonatal seizures (BFNS). A few reports on patients with a KCNQ2 mutation with a more severe outcome exist, but a definite relationship has not been established. In this study we investigated whether KCNQ2/3 mutations are a frequent cause of epileptic encephalopathies with an early onset and whether a recognizable phenotype exists.
methodsWe analyzed 80 patients with unexplained neonatal or early-infantile seizures and associated psychomotor retardation for KCNQ2 and KCNQ3 mutations. Clinical and imaging data were reviewed in detail.
resultsWe found 7 different heterozygous KCNQ2 mutations in 8 patients (8/80; 10%); 6 mutations arose de novo. One parent with a milder phenotype was mosaic for the mutation. No KCNQ3 mutations were found. The 8 patients had onset of intractable seizures in the first week of life with a prominent tonic component. Seizures generally resolved by age 3 years but the children had profound, or less frequently severe, intellectual disability with motor impairment. Electroencephalography (EEG) at onset showed a burst-suppression pattern or multifocal epileptiform activity. Early magnetic resonance imaging (MRI) of the brain showed characteristic hyperintensities in the basal ganglia and thalamus that later resolved.
interpretationKCNQ2 mutations are found in a substantial proportion of patients with a neonatal epileptic encephalopathy with a potentially recognizable electroclinical and radiological phenotype. This suggests that KCNQ2 screening should be included in the diagnostic workup of refractory neonatal seizures of unknown origin.
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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.