title: 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 occurred in 9 of 10 cases with a mean onset of 5.8 years. Convulsive and nonconvulsive status epilepticus were later features (6/10, mean onset 9 years). Tonic (40%) and atonic (30%) seizures also occurred. In 3 cases, an unusual seizure type, the atonic-myoclonic-absence was captured on video. A phenotypic spectrum was identified with 7 cases having moderate to severe intellectual disability and refractory seizures including tonic attacks. Their mean age at onset was 23 months. Three cases had a later age at onset (34 months) with relative preservation of intellect and an initial response to antiepileptic medication.
  
  
  CONCLUSIONS
  The phenotypic spectrum of CHD2 encephalopathy has distinctive features of myoclonic epilepsy, marked clinical photosensitivity, atonic-myoclonic-absence, and intellectual disability ranging from mild to severe. Recognition of this genetic entity will permit earlier diagnosis and enable the development of targeted therapies.
authors: From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia.
authors: Rhys H
authors: RH
authors: Thomas
authors: From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia.
authors: Lin Mei
authors: LM
authors: Zhang
authors: From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia.
authors: Gemma L
authors: GL
authors: Carvill
authors: From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia.
authors: John S
authors: JS
authors: Archer
authors: From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia.
authors: Sinéad B
authors: SB
authors: Heavin
authors: From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia.
authors: Simone A
authors: SA
authors: Mandelstam
authors: From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia.
authors: Dana
authors: D
authors: Craiu
authors: From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia.
authors: Samuel F
authors: SF
authors: Berkovic
authors: From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia.
authors: Deepak S
authors: DS
authors: Gill
authors: From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia.
authors: Heather C
authors: HC
authors: Mefford
authors: From the Epilepsy Research Centre (R.H.T., L.M.Z., J.S.A., S.B.H., S.A.M., S.F.B., I.E.S.), University of Melbourne, Austin Health, Heidelberg, Australia; MRC Centre for Neuropsychiatric Genetics & Genomics (R.H.T.), Hadyn Ellis Building, Cathays, Cardiff University, UK; Department of Neurology (L.M.Z.), Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics (G.L.C., H.C.M.), Division of Genetic Medicine, University of Washington, Seattle; Florey Institute of Neuroscience and Mental Health (S.A.M., I.E.S.), Melbourne, Australia; Departments of Radiology and Paediatrics (S.A.M., I.E.S.), Royal Children's Hospital, and University of Melbourne, Australia; Carol Davila University of Medicine (D.C.), Pediatric Neurology Clinic, Al Obregia Hospital, Bucharest, Romania; and TY Nelson Department of Neurology (D.S.G.), The Children's Hospital at Westmead, Sydney, Australia. scheffer@unimelb.edu.au.
authors: Ingrid E
authors: IE
authors: Scheffer
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D015331:Cohort Studies; D004268:DNA-Binding Proteins / Q000235:genetics*; D004831:Epilepsies, Myoclonic / Q000175:diagnosis* / Q000235:genetics* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation / Q000009:adverse effects*; D012640:Seizures / Q000175:diagnosis* / Q000235:genetics* / Q000503:physiopathology; D055815:Young Adult
chemical_list: C575189:CHD2 protein, human; D004268:DNA-Binding Proteins