Cytogenomic microarray analysis, which can involve comparative genomic hybridization and cytogenomic constitutional microarray analysis, has emerged as a novel diagnostic tool for individuals with unexplained developmental delay, autism spectrum disease, and mental retardation.
aCGH is used in addition to clinical evaluation and conventional genetic testing.
CMA, reports the Mayo Clinic, has quickly moved from research to the clinical setting and has emerged as the recommended first-tier postnatal test for individuals with multiple anomalies not specific to a well-delineated genetic syndrome, apparently nonsyndromic developmental delay/intellectual disability, and autism spectrum disorder.
Chromosomal microarray testing detects a genetic cause for these clinical features in 15-20% of cases, a substantial increase in the diagnostic yield in this patient population.
In a communique, “Clinical Utility of Chromosomal Microarray Testing,” the Mayo Clinic warns that the interpretation of chromosomal microarray test results is a “Complex and evolving process that is aided by collaboration between the clinician and clinical laboratory, particularly regarding the submission of detailed clinical information at the time of test referral. A genetic consultation is often of benefit to ensure the appropriate clinical interpretation of chromosomal microarray test results.”
To address these issues, the International Standards for Cytogenomic Arrays Consortium, now consisting of about 160 international laboratories, including the Mayo Clinic, was formed with the goals of developing evidence-based standards for chromosomal microarray design, to build a public database of clinical array data as a resource for the clinical and research communities, and to utilize the database to develop standards and guidelines for the interpretation of copy number changes in the clinical setting.
Hopefully, organizations such as the ISCA consortium will continue to work with scientists and clinicians in facilitating interpretation of a whole new world of data and enable the clinical utility of advanced cytogenomic tools.