title: The usefulness of array comparative genomic hybridization in clinical diagnostics of intellectual disability in children.
abstract: BACKGROUND
  Intellectual disability (ID)/Developmental delay (DD), which occurs in 1-3% of the population, accounts for a large number of cases regularly seen in genetics clinics. Currently, Array Comparative Genomic Hybridization (array CGH) is recommended by the International Standards for Cytogenomic Arrays (ISCA) Consortium as a first line test in the diagnostics of ID/DD, replacing G-banded chromosome analysis.
  
  
  OBJECTIVE
  Application of array CGH in clinical diagnostics of developmental delay/ intellectual disability in children.
  
  
  METHODS
  We present the results of 8x60K oligonucleotide array application that was successfully implemented in a cohort of 112 patients with the clinical diagnosis of intellectual disability and accompanying dysmorphic features and/or congenital malformations.
  
  
  RESULTS
  We have identified 37 copy number variants (CNVs) with the size ranging from 40 kb to numerical chromosomal aberrations, including unbalanced translocations and chromosome Y disomy, receiving an overall diagnostic yield of 33%. Known pathogenic changes were identified in 21.4% of the cases. Among patients with pathogenic CNVs identified by array CGH, 41.7% had a previously normal karyotype analysis.
  
  
  CONCLUSIONS
  Our studies provide more insights into the benefits derived by using chromosomal microarray analysis and demonstrate the usefulness of array CGH as a first-tier clinical setting test in patients with intellectual disability.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Bartnik
authors.affiliation: Zakład Genetyki Medycznej, Instytut Matki i Dziecka, ul. Kasprzaka 17a, 01-211 Warszawa, tel. (022) 32 77 145, e-mail: barbara.wisniowiecka@imid.med.pl, e-mail: barbara-wisniowiecka@tlen.pl.
authors.forename: Barbara
authors.initials: B
authors.lastname: Wiśniowiecka-Kowalnik
authors.forename: Beata
authors.initials: B
authors.lastname: Nowakowska
authors.forename: Marta
authors.initials: M
authors.lastname: Smyk
authors.forename: Marta
authors.initials: M
authors.lastname: Kędzior
authors.forename: Katarzyna
authors.initials: K
authors.lastname: Sobecka
authors.forename: Anna
authors.initials: A
authors.lastname: Kutkowska-Kaźmierczak
authors.forename: Jakub
authors.initials: J
authors.lastname: Klapecki
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Szczałuba
authors.forename: Jennifer
authors.initials: J
authors.lastname: Castañeda
authors.forename: Paweł
authors.initials: P
authors.lastname: Własienko
authors.forename: Natalia
authors.initials: N
authors.lastname: Bezniakow
authors.forename: Ewa
authors.initials: E
authors.lastname: Obersztyn
authors.forename: Ewa
authors.initials: E
authors.lastname: Bocian
mesh_terms: D000015:Abnormalities, Multiple / Q000175:diagnosis* / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D057215:Body Dysmorphic Disorders / Q000175:diagnosis / Q000235:genetics; D002648:Child; D002675:Child, Preschool; D002869:Chromosome Aberrations; D055028:Comparative Genomic Hybridization / Q000379:methods*; D056915:DNA Copy Number Variations; D002658:Developmental Disabilities / Q000175:diagnosis* / Q000235:genetics*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000175:diagnosis* / Q000235:genetics*; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D055815:Young Adult