title: Array comparative genomic hybridization: results from an adult population with drug-resistant epilepsy and co-morbidities.
abstract: BACKGROUND
  The emergence of array comparative genomic hybridization (array CGH) as a diagnostic tool in molecular genetics has facilitated recognition of microdeletions and microduplications as risk factors for both generalised and focal epilepsies. Furthermore, there is evidence that some microdeletions/duplications, such as the 15q13.3 deletion predispose to a range of neuropsychiatric disorders, including intellectual disability (ID), autism, schizophrenia and epilepsy. We hypothesised that array CGH would reveal relevant findings in an adult patient group with epilepsy and complex phenotypes.
  
  
  METHODS
  82 patients (54 from the National Hospital for Neurology and Neurosurgery and 28 from King's College Hospital) with drug-resistant epilepsy and co-morbidities had array CGH. Separate clinicians ordered array CGH and separate platforms were used at the two sites.
  
  
  RESULTS
  In the two independent groups we identified copy number variants judged to be of pathogenic significance in 13.5% (7/52) and 20% (5/25) respectively, noting that slightly different selection criteria were used, giving an overall yield of 15.6%. Sixty-nine variants of unknown significance were also identified in the group from the National Hospital for Neurology and Neurosurgery and 5 from the King's College Hospital patient group.
  
  
  CONCLUSIONS
  We conclude that array CGH be considered an important investigation in adults with complicated epilepsy and, at least at present for selected patients, should join the diagnostic repertoire of clinical history and examination, neuroimaging, electroencephalography and other indicated investigations in generating a more complete formulation of an individual's epilepsy.
authors.affiliation: Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London, United Kingdom.
authors.forename: Elizabeth C
authors.initials: EC
authors.lastname: Galizia
authors.forename: Maithili
authors.initials: M
authors.lastname: Srikantha
authors.forename: Rodger
authors.initials: R
authors.lastname: Palmer
authors.forename: Jonathan J
authors.initials: JJ
authors.lastname: Waters
authors.forename: Nicholas
authors.initials: N
authors.lastname: Lench
authors.forename: Caroline Mackie
authors.initials: CM
authors.lastname: Ogilvie
authors.forename: Dalia
authors.initials: D
authors.lastname: Kasperavičiūtė
authors.forename: Lina
authors.initials: L
authors.lastname: Nashef
authors.forename: Sanjay M
authors.initials: SM
authors.lastname: Sisodiya
mesh_terms: D000015:Abnormalities, Multiple / Q000453:epidemiology / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002869:Chromosome Aberrations; D002877:Chromosomes, Human / Q000235:genetics; D015331:Cohort Studies; D015897:Comorbidity; D055028:Comparative Genomic Hybridization; D002658:Developmental Disabilities / Q000453:epidemiology / Q000235:genetics; D004351:Drug Resistance; D004827:Epilepsy / Q000188:drug therapy / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D005796:Genes; D006801:Humans; D008607:Intellectual Disability / Q000453:epidemiology / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009154:Mutation; D055815:Young Adult