Subway's tuna sandwiches have ‘no amplifiable tuna DNA,’ NYT test reportedly finds

Amid a lawsuit that raises questions about what Subway’s tuna fish is made of, The New York Times said it submitted samples from three Los Angeles locations of the sandwich chain to have the fish tested.

The results showed there was “no amplifiable tuna DNA” in the samples, according to the Times, which said this means the lab was unable to identify any five tuna species it tested for. The Food and Drug Administration lists 15 species of fish that can be labeled tuna, the paper reported.

Two plaintiffs on a California lawsuit, who initially alleged in Jan. 21 court documents that Subway’s tuna sandwiches do not actually contain tuna but instead a “mixture of various concoctions,” have now scaled back on those claims in new court filings from June 7. The plaintiffs, Karen Dhanowa and Nilima Amin, now accuse the chain of misleading its customers by promoting its product as “100% sustainably caught skipjack and yellowfin tuna” or “100% tuna.”

Related: Two customers allege that Subway's tuna sandwiches aren't actually made with tuna, but a "mixture of various concoctions."

In a statement responding to the original lawsuit, Subway said in January “there simply is no truth to the allegations” and it will “vigorously defend itself” against the suit.

When contacted by Subway about the Times' report and the amended lawsuit, a spokesperson told TODAY by email Wednesday: "Just like the original claim, the new claims are untrue and have absolutely no merit. In fact, the amended complaint does not remedy any of the fundamental flaws in the plaintiffs’ case that should result in the case being dismissed."

As for the test results of the tuna, a spokesperson of the lab offered the Times two possible explanations: “One, it’s so heavily processed that whatever we could pull out, we couldn’t make an identification. Or we got some and there’s just nothing there that’s tuna.”

Related: Subway wants to prove that its tuna is the real deal — by getting you to taste it.

As the Times noted, when tuna is cooked, its DNA becomes denatured, which means the structure of the protein is changed and thus the test results can be inaccurate.

The Times said that before the test, the lab had been “wary about the challenges of identifying a fish that’s been cooked at least once, mixed with mayo, frozen and shipped across the country.”

These points were addressed by the Subway spokesperson in their email to TODAY, saying the Times' report "indicates that DNA testing is an unreliable methodology for identifying processed tuna."

"All (the test) says is that the testing could not confirm tuna, which is what one would expect from a DNA test of denatured proteins," the spokesperson added.

Subway’s website states the company only sources tuna from fisheries “with non-threatened stock levels,” and only uses skipjack and yellowfin tuna, as the Times noted.

Related: The 40-year-old singer and entrepreneur had the perfect reaction to the Subway tuna lawsuit.

In the court filings from June 7, the plaintiffs say those statements by Subway are false and “(duped) them into buying premium priced food dishes.”

“Had Plaintiffs and other consumers known the Products actually did not contain 100% tuna that was sustainably caught skipjack and yellowfin tuna and further that the tuna product did not contain ‘tuna species that come from anything less than healthy stocks, for example Albacore and Tongol,’” the lawsuit states, “they would not have purchased the Products or would have paid significantly less for them. As a result, Plaintiffs and other similarly situated class members have been deceived and suffered economic injury.”

The Times' report also discusses an issue of mislabeling, which the lawsuit also alleges, and points to an investigation conducted 2010-2012 by the ocean advocacy group Oceana that found seafood such as cod and snapper is often mislabeled and swapped for cheaper, less appealing fish 26-87% of the time.