The Diagnostic Yield of Array Comparative Genomic Hybridization Is High Regardless of Severity of Intellectual Disability/Developmental Delay in Children

J Child Neurol. 2016 May;31(6):691-9. doi: 10.1177/0883073815613562. Epub 2015 Oct 28.


Microarray-based comparative genomic hybridization is a method of molecular analysis that identifies chromosomal anomalies (or copy number variants) that correlate with clinical phenotypes. The aim of the present study was to apply a clinical score previously designated by de Vries to 329 patients with intellectual disability/developmental disorder (intellectual disability/developmental delay) referred to our tertiary center and to see whether the clinical factors are associated with a positive outcome of aCGH analyses. Another goal was to test the association between a positive microarray-based comparative genomic hybridization result and the severity of intellectual disability/developmental delay. Microarray-based comparative genomic hybridization identified structural chromosomal alterations responsible for the intellectual disability/developmental delay phenotype in 16% of our sample. Our study showed that causative copy number variants are frequently found even in cases of mild intellectual disability (30.77%). We want to emphasize the need to conduct microarray-based comparative genomic hybridization on all individuals with intellectual disability/developmental delay, regardless of the severity, because the degree of intellectual disability/developmental delay does not predict the diagnostic yield of microarray-based comparative genomic hybridization.

Keywords: array-CGH; developmental delay; intellectual disability.

MeSH terms

  • Brain / diagnostic imaging
  • Child
  • Child, Preschool
  • Chromosome Aberrations
  • Comparative Genomic Hybridization / methods*
  • DNA Copy Number Variations / genetics*
  • Developmental Disabilities / diagnostic imaging
  • Developmental Disabilities / genetics*
  • Electroencephalography
  • Female
  • Humans
  • Infant
  • Infant, Newborn
  • Intellectual Disability / diagnostic imaging
  • Intellectual Disability / genetics*
  • Logistic Models
  • Male
  • Microarray Analysis
  • Retrospective Studies
  • Severity of Illness Index