CHD2 myoclonic encephalopathy is frequently associated with self-induced seizures

Abstract

OBJECTIVE: To delineate the phenotype of early childhood epileptic encephalopathy due to de novo mutations of CHD2, which encodes the chromodomain helicase DNA binding protein 2. METHODS: We analyzed the medical history, MRI, and video-EEG recordings of 9 individuals with de novo CHD2 mutations and one with a de novo 15q26 deletion encompassing CHD2. RESULTS: Seizures began at a mean of 26 months (12-42) with myoclonic seizures in all 10 cases. Seven exhibited exquisite clinical photosensitivity; 6 self-induced with the television. Absence seizures occurred in 9 patients including typical (4), atypical (2), and absence seizures with eyelid myoclonias (4). Generalized tonic-clonic seizures oc..