Yonsei Med J.  2018 May;59(3):431-437. 10.3349/ymj.2018.59.3.431.

Phenotypic Analysis of Korean Patients with Abnormal Chromosomal Microarray in Patients with Unexplained Developmental Delay/Intellectual Disability

  • 1Department of Pediatrics, Gachon University Gil Medical Center, Incheon, Korea.
  • 2Department of Rehabilitation Medicine, Konyang University College of Medicine, Daejeon, Korea.
  • 3Department of Pediatrics, Konyang University College of Medicine, Daejeon, Korea.
  • 4Green Cross Genome, Yongin, Korea.
  • 5Department of Medical Genetics, Konyang University College of Medicine, Daejeon, Korea. raredisease@hanmail.net


The present study aimed to investigate chromosomal microarray (CMA) and clinical data in patients with unexplained developmental delay/intellectual disability (DD/ID) accompanying dysmorphism, congenital anomalies, or epilepsy. We also aimed to evaluate phenotypic clues in patients with pathogenic copy number variants (CNVs).
We collected clinical and CMA data from patients at Konyang University Hospital between September 2013 and October 2014. We included patients who had taken the CMA test to evaluate the etiology of unexplained DD/ID.
All of the 50 patients identified had DD/ID. Thirty-nine patients had dysmorphism, 19 patients suffered from epilepsy, and 12 patients had congenital anomalies. Twenty-nine of the 50 patients (58%) showed abnormal results. Eighteen (36%) were considered to have pathogenic CNVs. Dysmorphism (p=0.028) was significantly higher in patients with pathogenic CNVs than in those with normal CMA. Two or more clinical features were presented by 61.9% (13/21) of the patients with normal CMA and by 83.3% (15/18) of the patients with pathogenic CMA.
Dysmorphism can be a phenotypic clue to pathogenic CNVs. Furthermore, pathogenic CNV might be more frequently found if patients have two or more clinical features in addition to DD/ID.


Chromosomal microarray; developmental delay; intellectual disability; dysmorphism

MeSH Terms

Intellectual Disability


  • Fig. 1 Comparison of phenotypes between the patients with pathogenic CNVs and normal CMA. Dysmorphism (p=0.028) was significantly more frequent in patients with pathogenic CNVs than in those with normal CMA. Autism (p=0.387), epilepsy (p=0.718), and microcephaly (p=0.921) were more frequent in patients with pathogenic CNVs than in patients with normal CMA, but the difference was not significant. CNVs, copy number variants; VOUS, variants of uncertain significance; CMA, chromosomal microarray; CNS, central nervous system; FTT, failure to thrive.


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