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Vials for the Moderna and Pfizer-BioNTech COVID-19 vaccines are displayed at a temporary clinic outside a high school in Exeter, N.H., on Feb. 25, 2021. (AP/Krupa) Vials for the Moderna and Pfizer-BioNTech COVID-19 vaccines are displayed at a temporary clinic outside a high school in Exeter, N.H., on Feb. 25, 2021. (AP/Krupa)

Vials for the Moderna and Pfizer-BioNTech COVID-19 vaccines are displayed at a temporary clinic outside a high school in Exeter, N.H., on Feb. 25, 2021. (AP/Krupa)

Tom Kertscher
By Tom Kertscher December 3, 2021

COVID-19 vaccines are not gene therapy and a Forbes article doesn’t say they are

If Your Time is short

  • The original headline on a Forbes opinion column said "The Vaccine Changes your DNA. A little bit," but the author, a Johns Hopkins University gene expert, quickly changed it to "Covid Vaccines Don’t Alter Your DNA," after getting reaction from readers.

  • The column itself attacks anti-vaccine activists and states that the vaccines do not alter DNA.

  • The author told PolitiFact that he was trying to explain that  the mixture of DNA in the body is different after vaccination just as it is different after a viral infection.

After an opinion column was published by Forbes, glee emanated from people who believed it to prove an often-disproven claim: that COVID-19 vaccines are actually gene therapy. 

"Pretty sure I got fact-checked for saying this months ago. It’s fine, it’s just a little gene therapy," tweeted New Jersey gym owner Ian Smith on Dec. 1, sharing a screengrab of the headline of the Forbes piece that read "Yes, The Vaccine Changes Your DNA. A Tiny Bit. That’s A Good Thing."

Smith soon added a "fact-check" to his post that debunked the claim that the vaccine is gene therapy. But not before a screenshot of Smith’s tweet — and other screenshots of the Forbes headline — took off on social media, with posters claiming the Forbes headline provided proof that the COVID-19 vaccines are gene therapy and/or alter your DNA. 

"WE TOLD YA!" read one published Dec. 2.

The posts were flagged as part of Facebook’s efforts to combat false news and misinformation on its News Feed. (Read more about our partnership with Facebook.)

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We have repeatedly debunked claims that the vaccines are gene therapy. 

In this instance, the article cited was a Nov. 29 opinion piece written by a genome expert, Johns Hopkins University biomedical engineering professor Steven Salzberg. And shortly after it was published, numerous scientists weighed in, highly critical of the headline choice and article. 

Salzberg, who says he is "fighting the anti-vax movement through my columns," soon changed the headline to read, "Covid Vaccines Don’t Alter Your DNA – They Help Choose Cells To Strengthen Your Immune Response."

What’s more, a full reading of the article would have made it clear that Salzberg was not suggesting anti-vaccine activists were accurate in their claims that the vaccine alters your DNA or that it’s gene therapy. Rather, he stated they were wrong — and argued in part that the U.S. Centers for Disease Control and Prevention oversimplified its explanation of what the vaccines do.

"Totally different from gene therapy," Salzberg said about the COVID-19 vaccines in a phone interview with PolitiFact. "Apples and oranges. Completely unrelated. The vaccine is not going in and making a change to your DNA."

Salzberg told PolitiFact the original headline was misinterpreted and he changed it within a couple of hours. "I was trying to draw people in with this headline," so that people understand that changes that occur as a result of the vaccines are good for their health, "but the message was lost on some people." 

"It’s kind of a technical point and I was being perhaps a little too cute," he said.

Vaccines don’t directly change DNA

Salzberg told PolitiFact that the point he was trying to make was that in tiny quantities, the mixture of DNA in the body is different after vaccination just as it is different after a viral infection, but the vaccine is not mutating DNA. "But that's kind of a subtle point," he said. "I’m just trying to educate people on what immunity is. There is something that had to change. If nothing changed, you wouldn’t have immunity." 

The article itself makes the case that the vaccines do not alter DNA.

Here’s how it begins:

"One of the common tropes among anti-vaxxers lately is that the Covid-19 vaccine ‘changes your DNA.’ Oh, the horrors!

"Do they even know what they mean by that? Almost certainly not. Anti-vaxxers generally have no idea how biology works; often they are so confused that I’m tempted to say they are not even wrong. Even when they are right about something, it’s for the wrong reasons."

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Later, the article makes a distinction:

"It’s true that COVID-19 vaccines don’t directly alter your DNA, and it’s true that they don’t invade the cell nucleus, where your DNA resides. But that’s not the full story….

"Remember that the whole point of a vaccine is to prevent future infections. That means that something in your body has to change, right?...

"So back to our original question: does the Covid-19 vaccine change your DNA? Not directly, no. But yes, thanks to your own immune system, the overall mixture of DNA in your body is a tiny bit altered after you get any vaccine. Your DNA is also changed every time you recover from an infection, including the common cold. But the only change is in the DNA of a tiny number of immune cells, which hang around as guardians against future infections. And that’s a good thing."

COVID-19 vaccines not gene therapy

As we’ve reported, the mRNA technology used by the Pfizer and Moderna COVID-19 vaccines does not amount to gene therapy.

Gene therapy involves modifying a person’s genes to cure or treat a disease. The COVID-19 vaccines do not alter your DNA.

"It's absolutely incorrect to say that vaccines are really gene therapy," Cindy Prins, clinical associate professor of epidemiology at the University of Florida, has told PolitiFact. "Vaccines don't make any changes to your own DNA, so they don't edit your own DNA like gene therapy does. They also don't replace any mutated genes in your body."

Our ruling

Social media posts claimed that COVID-19 vaccines are gene therapy and a recent Forbes article proves that.

The vaccines do not amount to gene therapy. Gene therapy involves modifying a person’s genes to cure or treat a disease. The COVID-19 vaccines do not alter your DNA.

The original headline on the Forbes article said "the vaccine changes your DNA a tiny bit," but was quickly changed by the author, a Johns Hopkins University gene expert, who said it was misinterpreted. He said in the article that the vaccines do not alter DNA and told PolitiFact they are not gene therapy.

We rate the post False.

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COVID-19 vaccines are not gene therapy and a Forbes article doesn’t say they are

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