Affymetrix, a manufacturer of DNA microarrays, has obtained marketing authorization from the US Food and Drug Administration (FDA) for its Affymetrix CytoScan Dx assay that can detect chromosomal variations which may be responsible for a child’s developmental delay or intellectual disability.

The CytoScan Dx assay, based on a blood sample, can analyze the entire genome at one time and detect large and small chromosomal changes

Affymetrix CytoScan Dx assay has been reviewed by the FDA through its de novo classification process, a regulatory pathway for some novel low-moderate-risk medical devices.

The FDA’s review of the CytoScan Dx assay included an analytical evaluation of the test’s ability to accurately detect numerous chromosomal variations of different types, sizes, and genome locations when compared to several analytically validated test methods.

In its review, the FDA found that the CytoScan Dx assay could analyze a patient’s entire genome and adequately detect chromosome variations in regions of the genome associated with intellectual and developmental disabilities.

FDA Center for Devices and Radiological Health Office of In-Vitro Diagnostics and Radiological Health director Dr Alberto Gutierrez noted this new tool may help in the identification of possible causes of a child’s developmental delay or intellectual disability, allowing health care providers and parents to intervene with appropriate care and support for the child.

"The FDA’s review of the test provides clinical laboratories with information about the expected performance of the device and the quality of the results," Dr Gutierrez added.

FDA’s review also included a study that compared the performance of the CytoScan Dx assay to tests that are commonly used for detecting chromosomal variations associated with a developmental delay or intellectual disability.

In the comparison of test results from 960 blood specimens, the CytoScan Dx assay demonstrated improved ability over commonly used tests that included karyotyping and FISH chromosomal tests.