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GTR Home > Tests > Standard karyotype (pediatric)

Performance Characteristics



  • Entire test performed in-house

Analytical Validity


This test is evaluated for analytical validity using an established validation process utilizing abnormal and normal specimens as per CAP, ACMG, and CLIA guidelines. For standard postnatal constitutional karyotype analysis 20 cells are counted, 5 cells analyzed, and 3 cells are karyotyped. In cases where mosaicism is suspected, additional cells are counted as indicated.



Assay Limitation(s)


A limitation of this test is that the structural abnormalities must be large enough to be visible under the microscope. The resolution of this technology – the minimum size of a missing or extra chromosome piece that can be visualized – is approximately 5-10 megabases (Mb).

Proficiency Testing (PT)

Is proficiency testing performed for this test? Help
Method used for proficiency testingHelp
Formal PT program
PT ProviderHelp
American College of Medical Genetics / College of American Pathologists, ACMG/CAP

FDA Regulatory Clearances of the Test

FDA Category Designation
FDA exercises enforcement discretion

Practice guidelines

  • NSGC, 2021
    National Society of Genetic Counselors Position Statement: Prenatal Cell-Free DNA Screening

Consumer resources

IMPORTANT NOTE: NIH does not independently verify information submitted to the GTR; it relies on submitters to provide information that is accurate and not misleading. NIH makes no endorsements of tests or laboratories listed in the GTR. GTR is not a substitute for medical advice. Patients and consumers with specific questions about a genetic test should contact a health care provider or a genetics professional.