Objective: To assess the value of chromosomal microarray analysis (CMA) for the diagnosis of children with intellectual disability/developmental delay (ID/DD) but a normal karytype.
Methods: Peripheral blood samples from 92 ID/DD patients were analyzed with CMA using Affymetrix CytoScan 750K arrays. The results were analyzed by ChAS v3.0 software.
Results: Eighteen cases (19.57%) were detected with abnormalities by CMA, among which 10 cases were diagnosed with microdeletion/microduplication syndromes. These included 2 Williams-Beuren syndromes, 2 Angelman syndromes, 2 Russell-Silver syndromes, 1 Smith-Magenis syndromes, 1 Wolf-Hirschhorn syndromes, 1 15q26 overgrowth syndrome and 1 Xq28 (MECP2) duplication syndrome. In addition, 8 cases were diagnosed with pathogenic copy number variations (pCNV).
Conclusion: CMA can significantly improve the diagnostic rate for patients with ID/DD, which is of great value for the treatment of such children and guidance of reproduction for their parents. Therefore, CMA should become the first-line diagnostic test for patients with ID/DD.