Novel mutation in STXBP1 gene in a patient with non-lesional Ohtahara syndrome

Abstract

Introduction: Ohtahara syndrome (OS, OMIM#308350, ORPHA1934) is an early-onset epileptic encephalopathy (EOEE) characterised by spasms, intractable seizures, suppression-burst pattern on the electroencephalogram, and severe psychomotor retardation. Mutations in STXBP1 -a gene that codes for syntaxin binding protein 1 and is involved in synaptic vesicle exocytosis- has been identified in most patients with OS.

Patient and results: We report the case of a 19-month-old child with OS who displays a previously unreported mutation in STXBP1 (c.1249+2T>C, G417AfsX7). This mutation is located in a donor splice site and eliminates exon 14, resulting in a truncated protein.

Conclusion: This previously unreported STXBP1 mutation in a subject with Ohtahara syndrome and non-lesional magnetic resonance imaging (MRI) broadens the mutational spectrum associated with this devastating epileptic syndrome.

Keywords: Clinical genetics; Early-onset epileptic encephalopathy; Encefalopatía epiléptica de inicio precoz; Epilepsia; Epilepsy; Genética clínica; Ohtahara syndrome; STXBP1; Síndrome de Ohtahara.