Emotion‐Induced Myoclonic Absence‐Like Seizures in a Patient with Inv‐Dup(15) Syndrome: A Clinical, EEG, and Molecular Genetic Study

Summary: We have described a clinical EEG and molecular genetic study of a 9‐year‐old boy with inv‐dup(15) syndrome in whom seizures were induced by emotionally gratifying stimuli. The reflex seizures began 5–20 s after the onset of repeated cheek‐kissing from his mother or after viewing of pleasant or funny events. They were characterized by bilateral discharges involving mainly the temporal regions and evolving into myoclonic absence‐like seizures. Nonemotional stimuli, such as a pinch, sucking or rubbing his cheeks, or the sound of the kiss alone, failed to provoke seizures. The seizures were resistant to antiepileptic (AED) treatments. Molecular genetic investigations revealed a correct methylation pattern of the chromosomes 15, and three copies (two maternal and one paternal) of the segment 15q11‐q13, including the GABRb3 gene. We hypothesize that an overexpression of cerebral γ‐aminobutyric acid (GABA)‐mediated inhibition accounts for the severe epilepsy that we observed in this patient.