title: Clinical and genetic features of 13 Spanish patients with KCNQ2 mutations.
abstract: The KCNQ2 gene codifies a subunit of the voltage-gated potassium M channel underlying the neuronal M-current. Classically, mutations in this gene have been associated with benign familial neonatal seizures, however, in recent years KCNQ2 mutations have been reported associated to early-onset epileptic encephalopathy. In this work, detailed familiar, clinical and genetic data were collected for 13 KCNQ2-positive patients revealed among a cohort of 80 epileptic pediatric probands from Spain who were analyzed through a targeted next-generation sequencing assay for 155 epilepsy-associated genes. This work shows for the first time the association between KCNQ2 mutations and startle attacks in 38% of patients, which opens the possibility to define electroclinical phenotypes associated to KCNQ2 mutations. It also demonstrates that KCNQ2 mutations contribute to an important percentage of Spanish patients with epilepsy. The study confirm the high genetic heterogeneity of this gene with 13 different mutations found, 10 of them novel and the better outcome of patients treated with sodium channel blockers.
authors.affiliation: Unit of Child Neurology, Department of Pediatrics, Hospital Infantil Universitario Niño Jesús de Madrid, Madrid, Spain.
authors.forename: Montesclaros
authors.initials: M
authors.lastname: Hortigüela
authors.affiliation: Unit of Diagnosis and Treatment of Inborn Errors of Metabolism (UDyTEMC), Health Research Institute of Santiago de Compostela (IDIS), Galicia, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Fernández-Marmiesse
authors.affiliation: Unit of Child Neurology, Department of Pediatrics, Hospital Infantil Universitario Niño Jesús de Madrid, Madrid, Spain.
authors.forename: Verónica
authors.initials: V
authors.lastname: Cantarín
authors.affiliation: Unit of Diagnosis and Treatment of Inborn Errors of Metabolism (UDyTEMC), Health Research Institute of Santiago de Compostela (IDIS), Galicia, Spain.
authors.forename: Sofía
authors.initials: S
authors.lastname: Gouveia
authors.affiliation: Unit of Child Neurology, Department of Pediatrics, Hospital Infantil Universitario Niño Jesús de Madrid, Madrid, Spain.
authors.forename: Juan J
authors.initials: JJ
authors.lastname: García-Peñas
authors.affiliation: Unit of Child Neurology, Department of Pediatrics, Hospital Sant Joan de Deu, Barcelona, Spain.
authors.forename: Carmen
authors.initials: C
authors.lastname: Fons
authors.affiliation: Biochemical, Genetics and Rett Unit, Laboratory Department, Hospital Sant Joan de Déu, Esplugues, Barcelona, Spain.
authors.forename: Judith
authors.initials: J
authors.lastname: Armstrong
authors.affiliation: Department of Pediatrics. Hospital Universitario de Canarias, Santa Cruz de Tenerife, Spain.
authors.forename: Desirée
authors.initials: D
authors.lastname: Barrios
authors.affiliation: Molecular Genetics Unit, Hospital Universitario de Canarias, Santa Cruz de Tenerife, Spain.
authors.forename: Felícitas
authors.initials: F
authors.lastname: Díaz-Flores
authors.affiliation: Unit of Child Neurology, Department of Pediatrics, Hospital Universitario la Paz, Madrid, Spain.
authors.forename: Pilar
authors.initials: P
authors.lastname: Tirado
authors.affiliation: Unit of Diagnosis and Treatment of Inborn Errors of Metabolism (UDyTEMC), Health Research Institute of Santiago de Compostela (IDIS), Galicia, Spain.|Centro de Investigación Biomédica de Enferemedades Raras (CIBERER), Instituto de Salud Carlos III, Spain.
authors.forename: María L
authors.initials: ML
authors.lastname: Couce
authors.affiliation: Unit of Child Neurology, Department of Pediatrics, Hospital Infantil Universitario Niño Jesús de Madrid, Madrid, Spain.
authors.forename: Luis G
authors.initials: LG
authors.lastname: Gutiérrez-Solana
mesh_terms: D001483:Base Sequence; D020936:Epilepsy, Benign Neonatal / Q000235:genetics*; D005190:Family; D020022:Genetic Predisposition to Disease; D006801:Humans; D007231:Infant, Newborn; D051658:KCNQ2 Potassium Channel / Q000235:genetics*; D009154:Mutation; D010641:Phenotype; D013216:Reflex, Startle / Q000235:genetics*; D017422:Sequence Analysis, DNA; D013030:Spain
chemical_list: D051658:KCNQ2 Potassium Channel