Genome-wide copy number variation analysis in idiopathic intellectual disability/multiple congenital anomalies: New array technologies have facilitated the analysis of submicroscopic chromosomal imbalances and structural variants. Copy number variation (CNV) analysis can reveal genetic imbalances in up to 10 % of cases involving intellectual disability (ID), with or without multiple congenital anomalies (MCA). Here we present 4 cases, diagnosed by CNV analysis using Affymetrix Genome Wide Human SNP 6.0 array, and their parents. CNVs ranging from 18 to 196 per subject, with a size range of 100kb-6093kb, were detected in all cases. One case revealed inherited CNVs, whilst de novo ins/dels were found in the other three which may be causative factors in the development of clinical pictures. Microarray technology may help to reveal the etiology of ID and is a potentially useful diagnostic tool for patients with ID/MCA.