Evaluation of the Affymetrix CytoScan(®) Dx Assay for developmental delay

The goal of molecular cytogenetic testing for children presenting with developmental delay (DD) is to identify or exclude genetic abnormalities that are associated with cognitive, behavioral and/or motor symptoms. Until 2010, chromosome analysis was the standard first-line genetic screening test for evaluation of patients with DD when a specific syndrome was not suspected. In 2010, The American College of Medical Genetics and several other groups recommended chromosomal microarray as the first-line test in children with DDs, multiple congenital anomalies and/or autism. This test is able to detect regions of genomic imbalances at a much finer resolution than G-banded karyotyping. Until recently, no chromosomal microarray testing had been approved by the US FDA. This article focuses on the use of the Affymetrix CytoScan(®) Dx Assay (Santa Clara, CA, USA), the first chromosomal microarray to receive FDA approval for the genetic evaluation of individuals with DD.