title: Genetic and epileptic features in Rett syndrome.
abstract: OBJECTIVE
  Rett syndrome is a severe neurodevelopmental disorder in females. Most have mutations in the methyl-CpG-binding protein 2 (MECP2) gene (80-90%). Epilepsy is a significant commonly accompanied feature in Rett syndrome. Our study was aimed at comprehensive analysis of genetic and clinical features in Rett syndrome patients, especially in regards to epileptic features.
  
  
  METHODS
  We retrospectively reviewed 20 patients who were diagnosed with MECP2 mutations at Severance Children's Hospital between January 1995 and July 2010. All patients met clinical criteria for Rett syndrome. Evaluations included clinical features, epilepsy classification, electroencephalography analysis, and treatment of seizures.
  
  
  RESULTS
  Ages ranged from 3.6 to 14.3 years (7.7±2.6). Fourteen different types of MECP2 mutations were found, including a novel in-frame mutation (1153-1188 del36). Fourteen of these patients (70.0%) had epilepsy, and the average age of seizure onset was 3.0±1.8 years. Epilepsy was diverse, including partial seizure in four patients (28.5%), secondarily generalized seizure in six (42.8%), generalized tonic seizure in two (14.3%), Lennox-Gastaut syndrome in one (7.1%), and myoclonic status in non-progressive encephalopathy in one (7.1%). Motor functions were delayed so that only 10 patients (50.0%) were able to walk independently: five (35.8%) in the epilepsy group and five (83.3%) in the non-epilepsy group. Average developmental scale was 33.5±32.8 in the epilepsy group and 44.4±21.2 in the non-epilepsy group. A clear genotype-phenotype correlation was not found.
  
  
  CONCLUSIONS
  There is a tendency for more serious motor impairment and cognitive deterioration in Rett syndrome patients with epilepsy.
authors.affiliation: Division of Pediatric Neurology, Department of Pediatrics, Pediatric Epilepsy Clinics, Severance Children's Hospital, Yonsei University College of Medicine, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-752, Korea.
authors.forename: Hyo Jeong
authors.initials: HJ
authors.lastname: Kim
authors.forename: Shin Hye
authors.initials: SH
authors.lastname: Kim
authors.forename: Heung Dong
authors.initials: HD
authors.lastname: Kim
authors.forename: Joon Soo
authors.initials: JS
authors.lastname: Lee
authors.forename: Young-Mock
authors.initials: YM
authors.lastname: Lee
authors.forename: Kyo Yeon
authors.initials: KY
authors.lastname: Koo
authors.forename: Jin Sung
authors.initials: JS
authors.lastname: Lee
authors.forename: Hoon-Chul
authors.initials: HC
authors.lastname: Kang
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004827:Epilepsy / Q000235:genetics* / Q000473:pathology*; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D051783:Methyl-CpG-Binding Protein 2 / Q000235:genetics*; D009154:Mutation; D010641:Phenotype; D012189:Retrospective Studies; D015518:Rett Syndrome / Q000235:genetics* / Q000473:pathology*
chemical_list: D051783:Methyl-CpG-Binding Protein 2