In response to an inquiry about DNA testing by Senators Orrin Hatch, R-Utah, and Martin Heinrich, D-N.M., submitted in late February, the Food and Drug Administration (FDA) notes that "if the FDA were to use DNA methods on botanical extracts, we would use them in combination with established chemical or other acceptable methods historically used to verify the identity."

FDA's response issued March 18, also notes that it has not stated that DNA barcode testing is inappropriate, but any evaluation would be based on a specific firm's methodology for the specific product and whether the testing was appropriate and scientifically valid. FDA stresses that it has not received the testing methodology or results from the New York Attorney General and can't address the validity of those testing results.

FDA also highlights current good manufacturing practice (cGMP) requirements that companies must conduct at least one appropriate test to confirm the identity of each incoming dietary ingredient before being used in a finished supplement and test finished product batches to verify that they meet established specifications for identity, purity, strength, composition, and limits on contamination.

Regarding labeling requirements, FDA states that labeling of unintentional, trace amounts of agricultural materials is not part of the ingredient labeling requirements, but the cGMP rule does address intentional and unintentional adulteration of finished products by establishing a production and process control system. 

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FDA responses to Sens. Hatch and Heinrich

Sens. Hatch and Heinrich's letter to FDA