One of the more pernicious tropes in the world of pseudoscience is that DNA in vaccines GMOs are going to magically incorporate into your cells changing you from a human into a sasquatch with ears of corn growing out of your head. Now that would be fun to see, but unless there’s a mad scientist out there trying to grow ears of corn out of a hirsute humane that looks like Sasquatch, it will probably never happen.
And most certainly consuming DNA in vaccines or eating GMOs with a new gene are not going to cause anything at all to any human I know.
But of course, science rarely gets in the way of good pseudoscience for anti-vaxxers and anti-GMO zealots. That’s why this old feathered skeptic in the dinosaur clade is here, to make sure the science is clear and to mock the pseudoscience.
What is this DNA thing?
Amateurs continue to imbue DNA with some magical properties that never made sense to me. Although the biochemistry of DNA is quite complex, I will endeavor to teach DNA 101 without causing any reader to rip his eyeballs out. I’ll do this in a bullet-point order just to make it easy.
- DNA, or deoxyribonucleic acid, contains four nitrogen-containing nucleobases,(cytosine [C], guanine [G], adenine [A] or thymine [T]), a sugar called deoxyribose, and a phosphate group. The nucleobases (or nucleic acids), C G A T, are like letters in a language. Of course, you might wonder how four letters can spell out the complex language of the proteins (genes only code for proteins that make every organism on the planet what they are).
- DNA is double-stranded, so one side acts as the “sense” strand while the other is the “anti-sense” strand. Furthermore, the nucleobases form very specific pairs – A on the sense side always pairs with T on the anti-sense side, and vice versa. And C on the sense side will always pairs with G on the anti-sense side, and vice versa again.
- Through a complicated process called transcription, the sense strand of DNA is then transcribed into a mirror image RNA or ribonucleic acid. RNA is very similar to DNA, except the thymine in DNA is replaced with uracil (U) in RNA. So during the transcription process, U will always pair with DNA T.
- Are you still with me? Well, we’re still not at the point where we’re making proteins. In a process called translation, groups of three nucleic acids tell the cell to add a unique amino acid into a chain. A long chain of these amino acids become a protein. Of course, this isn’t a random set of nucleic acids, there is a start and endpoint for translation. Thus, just four nucleic acid letters create amino acid words that form a unique combination to become the protein word. I hope that I didn’t mess up that metaphor.
- DNA and RNA are manufactured in each cell from basic ingredients such as the sugars ribose and deoxyribose and other components. There is not a central manufacturer of nucleic acids in the body. Furthermore, DNA, RNA or individual nucleic acids rarely float in the blood, and even if the did, cells cannot usually transport them into the cell. Even if they could, the cell would catabolize them, reuse them, or expel them from the cell.
- All DNA and RNA molecules across every organism on the planet are exactly the same. Yes, each organism’s genes are a different combination of the four letters, but the individual nucleic acids are exactly the same. And the same three-letter DNA group encodes for the same amino acid in every organism.
- In case all of the above is not clear, human DNA contains the same biochemicals as lowly cyanobacteria.
I know those of us who actually were biochemists or cell biologists (or both) are offended that I converted DNA biochemistry into 500 words or so. This goes back to my article that states that becoming an expert in these areas takes thousands of hours of classwork and experience.
Now, if you really want to dig into DNA, read Professor Alan McHughen‘s new book, DNA Demystified, because he tells the full story of DNA in a few thousand words. And it is fascinating.
That pesky DNA in GMOs will harm you
Those pseudoscience tropes like DNA in vaccines and weird DNA in agricultural crops are some of the basis of attacking vaccines and GMOs. So, let’s start with GMOs, then we’ll head to the DNA in vaccines.
When you bite into that ear of corn or genetically modified salmon, you are eating complex food made up of proteins, fats, carbohydrates, and, yes, DNA. But I’ve noticed something when I read the pseudoscience websites – there’s this belief that when you eat food, magically the whole protein or carbohydrates moves from your gut to your blood without many transformations. Nothing could be further from science.
Based on our knowledge of the digestive process, fats, DNA, carbohydrates, and proteins are broken down into their simplest components, and specialized transport systems move these simple components across the barrier between the digestive tract and blood. They have evolved to not transport full-size molecules, partially because the blood is incapable of carrying large foreign molecules (and could induce an immune response).
Moreover, small constituent molecules, like amino acids instead of the whole protein, or glucose instead of a long-chain carbohydrate, are more easily transported to locations in the body to be then used as fuel or building blocks for new proteins and DNA. We just have not seen a mechanism in the digestive tract that can move large molecules, like gene-length DNA fragments, into the bloodstream.
In case you’re wondering, micronutrients, like certain vitamins, are very small and there are specific mechanisms to move those from the food you have consumed into the bloodstream.
Debunking GMO DNA causes harm
Are the anti-GMO people correct in assuming that GMO genes transfer to humans? Well, let’s look at the data:
- But let’s assume that there’s some unknown, mysterious mechanism that allows DNA to be transmitted into the blood (while excluding long-chain carbohydrates, whole proteins, and other large molecules). The numbers are so small, just a handful of complete genes, that the probability that those DNA molecules will have any effect on the body is near 0.
- Genes don’t easily jump from one species to another. If gene transfer were so simple, the medical usefulness of gene therapy would be extremely high, instead of being incredibly difficult. We’re trying to transfer genes to cure diseases, and we’re finding it almost impossible. If consuming a few kernels of corn, introduced some gene into the bloodstream that somehow gets incorporated into the human genome, well that would be a miracle.
- But the most important thing is that if there is some heretofore mysterious mechanism to transfer DNA from the digestive tract to the human genome, it should be noted that nearly everything we consume contains DNA. The plausibility that any number of DNA fragments from hamburger, salads, cereal, eggs, or the billion other foods will eat getting into the bloodstream is nearly non-existent. There is no evidence that we ever incorporate genes from corn. Or lettuce. Or salmon. Or a chicken. There is just no evidence of it.
As Professor McHughen wrote:
A more direct and long-term test involves considering what happens to animals fed GMOs intensively and over long periods, including multiple generations. Dr. Alison Van Eenennaam from the University of California, Davis, conducted such a study, involving over 100 billion animals, and showed no health or productivity concerns. This is a particularly powerful and compelling study, because unlike humans—who cannot be subject to long-term dietary safety testing—animals can be fed GMO feeds intensively, extensively, and continuously over long time spans. If there were unexpected problems with GMO foods or feeds, those problems would certainly appear in the test animals. The fact that none did provides a high degree of assurance and confidence.
In other words, we have done massive studies in animals, and the evidence that there is no effect from GMO foods, so even if we’re consuming some strange DNA in our salmon or corn, it’s not going to magically incorporate itself into the DNA in every one of the 50 trillion cells in an average human.
That pesky DNA in vaccines trope
At this point, the pseudoscience-loving anti-vaxxer will say to me, “OK, maybe you convinced me that eating yucky DNA in corn isn’t going to harm me, but vaccines are injected! Gotcha!”
The anti-vaxxers love to claim that billions or TRILLIONS!! of DNA fragments can be found in the MMR or chickenpox vaccines, respectively. One quack science Wow, that sounds like a lot. I’m scared, are you scared?
Take a breath, we’re all about science here. This is just more anti-vaccine pseudoscience.
- We have no evidence, none, that there are that many DNA “fragments” in each vaccine. Where is the data from? Is it peer-reviewed? Has any legitimate scientist published this? Actually, no. But we’ll get to that.
- In an average human being, there are over 50 trillion cells each with 3 billion DNA base pairs. That’s 1,500,000,000,000,000,000,000,000 DNA base pairs in an average human. So, even the worst-case scenario, 8 trillion fragments would only represent about 0.000000000533333% of the DNA in every human.
- DNA is highly unstable – it breaks down into nonsense fragments. And remember, DNA codes into proteins only in a logical manner – the cell must know where to start and where to end on the DNA strand to create a protein. This is non-negotiable.
- As we wrote above, DNA rarely moves from the blood into cells. Despite the odd beliefs of pseudoscience-pushing anti-vaxxers, real science tells us that there must be carrier proteins to move substances into cells – it does not happen passively. Cell biology is infinitely more complicated than most people believe.
- Foreign DNA does not incorporate itself into one’s genome. This has been debunked so many times, but let’s just be logical. We eat corn, and we don’t turn into corn. We have a microbiome made up of thousands of non-human organisms, and we don’t become those organisms. And gene therapy has not worked very well, because we have a difficult time trying to get genes inserted into human genomes.
- Let’s think about blood transfusions which contain all kinds of DNA fragments. Has anyone turned into another person as a result of this – how many millions of transfusions are done every year, and we have not one single case report of someone suddenly becoming a new person after receiving that DNA.
- DNA “fragments” are meaningless to science and to the body’s biochemistry. Genes aren’t just random chains of DNA, they are quite complex with all kinds of information on how the body is to produce a protein.
- DNA “fragments” do not cause autoimmune diseases – the body is filled with DNA fragments from one’s self and from all the organisms that populate us, The immune system pretty much ignores it.
- Free DNA is broken down rather rapidly by enzymes called DNases, so any DNA floating around your blood is not going to suddenly enter every single cell in your body and turn you into Sasquatch.
Let’s be clear about this – the DNA in vaccines trope is just used to cause fear, uncertainty, and doubt in people who may be considering a vaccine. It is unscientific and human biochemistry is just laughing hysterically. If it could do so.
Debunking with science
In an article by H Yang et al, published in the journal Vaccine, the researchers examined the oncogenic and infective potential of residual host cell DNA from a cell-based live, attenuated influenza vaccine that is manufactured in Madin Darby Canine Kidney (MDCK) cells. They concluded that 230 billion doses of vaccine would need to be administered before an oncogene dosage equivalent would be reached, and 83 trillion doses would need to be administered to induce an infective event. In other words, it’s not going to happen.
In another article by H Yang et al, published in the Journal of Biopharmaceutical Statistics, the authors concluded that the calculated probability of having one oncogenic or infective event based on the WHO/FDA limits for DNA in vaccines is less than 10-15. In other words, one chance in 1,000,000,000,000,000 vaccines.
In an article by Wierenga et al., published in the journal Biologicals, the authors followed animals for 8 years after receiving over 1 million times the DNA allowed in vaccines by WHO. None of these animals showed any evidence of tumor formation.
Notes – DNA vaccines
If someone is Googling “DNA in vaccines,” most of the hits will be actual “DNA vaccines.” It is a theoretical type of vaccine (none have been approved yet) that uses a unique method to induce an immune response.
Basically, a gene that expresses a specific antigen from an infectious disease will be inserted into a harmless virus, like adenovirus. To be clear, this virus is carrying one gene from the pathogen into the cell. Then the cell is temporarily hijacked to produce that antigen.
Once that antigen gets into the bloodstream it induces an adaptive immune response which should then protect the person from that disease. Theoretically, this can produce a more robust immune response than typical vaccine methods, although we are a long way from knowing this.
But the key point here is that the DNA vaccine isn’t injecting bits of DNA to randomly be incorporated into cells – that wouldn’t work, because, as we wrote, bits of DNA cannot just enter cells at will. This DNA is a full gene that’s inside of the virus – it “carries” the gene and injects it into cells.
Anyway, this is a tiny bit of background on DNA vaccines that have nothing to do with the DNA in vaccines trope. And as of today, there are no approved DNA vaccines, so when one appears close to being approved by the FDA, I’m sure we’ll talk about it in more detail.
There is no scientifically plausible reason to accept the hypothesis that either DNA in vaccines or the DNA in GMO foods are dangerous. In the case of GMOs, ALL of the DNA in food that is absorbed is in the form of the four basic nucleotides, the same ones that the body uses to make its own DNA.
In the case of DNA in vaccines, it’s the same story. Whatever DNA that’s in the vaccines are going to be broken down into simple nucleotides within a few minutes. And even if those foreign DNA fragments were going to be absorbed by cells (they don’t), they are not going to be incorporated in any way into the genes of that cell. It’s not how the machinery of the cell works.
That Sasquatch DNA in the vaccines (OK, it’s not, but whatever DNA that’s in there) is indistinct. It’s not whole genes, it’s nonsense DNA fragments that don’t tell the cell anything. And no, those fragments are not going to induce an allergic reaction, because there are DNA fragments everywhere that are constantly being recycled.
This is the frustration that many of us have with the science deniers everywhere – they are missing basic scientific information that would allow anyone with that information to reject most of the claims.
GMOs are safe. Vaccines are safe. That’s settled science. You will not turn into Sasquatch with ears of corn growing out of your head if you GMO food and get injected with that DNA in vaccines.
- Wierenga DE, Cogan J, Petricciani JC. Administration of tumor cell chromatin to immunosuppressed and non-immunosuppressed non-human primates. Biologicals. 1995 Sep;23(3):221-4. doi: 10.1006/biol.1995.0036. PubMed PMID: 8527121.
- Yang H, Wei Z, Schenerman M. A statistical approach to determining criticality of residual host cell DNA. J Biopharm Stat. 2015;25(2):234-46. doi: 10.1080/10543406.2014.972514. PubMed PMID: 25358029.
- Yang H, Zhang L, Galinski M. A probabilistic model for risk assessment of residual host cell DNA in biological products. Vaccine. 2010 Apr 26;28(19):3308-11. doi: 10.1016/j.vaccine.2010.02.099. Epub 2010 Mar 10. PubMed PMID: 20226252.