title: Early onset absence epilepsy: 1 in 10 cases is caused by GLUT1 deficiency.
abstract: Glucose transporter 1 (GLUT1) deficiency caused by mutations of SLC2A1 is an increasingly recognized cause of genetic generalized epilepsy. We previously reported that >10% (4 of 34) of a cohort with early onset absence epilepsy (EOAE) had GLUT1 deficiency. This study uses a new cohort of 55 patients with EOAE to confirm that finding. Patients with typical absence seizures beginning before 4 years of age were screened for solute carrier family 2 (facilitated glucose transporter), member 1 (SLC2A1) mutations or deletions. All had generalized spike-waves on electroencephalography (EEG). Those with tonic and/or atonic seizures were excluded. Mutations were found in 7 (13%) of 55 cases, including five missense mutations, an in-frame deletion leading to loss of a single amino acid, and a deletion spanning two exons. Over both studies, 11 (12%) of 89 probands with EOAE have GLUT1 deficiency. Given the major treatment and genetic counseling implications, this study confirms that SLC2A1 mutational analysis should be strongly considered in EOAE.
authors.affiliation: Epilepsy Research Centre, Department of Medicine, University of Melbourne, Austin Health, Melbourne, Victoria, Australia.
authors.forename: Todor
authors.initials: T
authors.lastname: Arsov
authors.forename: Saul A
authors.initials: SA
authors.lastname: Mullen
authors.forename: John A
authors.initials: JA
authors.lastname: Damiano
authors.forename: Kate M
authors.initials: KM
authors.lastname: Lawrence
authors.forename: Linda L
authors.initials: LL
authors.lastname: Huh
authors.forename: Melinda
authors.initials: M
authors.lastname: Nolan
authors.forename: Helen
authors.initials: H
authors.lastname: Young
authors.forename: Anaïs
authors.initials: A
authors.lastname: Thouin
authors.forename: Hans-Henrik M
authors.initials: HH
authors.lastname: Dahl
authors.forename: Samuel F
authors.initials: SF
authors.lastname: Berkovic
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Crompton
authors.forename: Lynette G
authors.initials: LG
authors.lastname: Sadleir
authors.forename: Ingrid E
authors.initials: IE
authors.lastname: Scheffer
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D002239:Carbohydrate Metabolism, Inborn Errors / Q000150:complications*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004252:DNA Mutational Analysis; D004832:Epilepsy, Absence / Q000209:etiology* / Q000235:genetics*; D019143:Evolution, Molecular; D005260:Female; D051272:Glucose Transporter Type 1 / Q000235:genetics; D006801:Humans; D008297:Male; D009004:Monosaccharide Transport Proteins / Q000172:deficiency; D009154:Mutation / Q000235:genetics*
chemical_list: D051272:Glucose Transporter Type 1; D009004:Monosaccharide Transport Proteins