Concerns about new technologies: Will mRNA vaccines change our genetic makeup?

Biontech / Pfizer and Moderna vaccines are considered effective drugs against Sars-CoV-2. Both are based on mRNA technology, where genetic material is delivered to human cells. Can this change the human genome? Fact check.
It doesn’t seem to be true. Innovative biotechnology can save humanity from the coronavirus. The first vaccine westernally approved by Biontech / Pfizer uses so-called mRNA. Previously, there was no approved vaccine of this type anywhere in the world. Not only was the vaccine developed in record time, but it was so effective at 95% that many scientists didn’t expect it. Moderna’s competitors are equally effective and are based on mRNA.

Abbreviation mRNA is an abbreviation for messenger ribonucleic acid and is also known as messenger RNA. mRNA vaccines consist of the genetic information of one or more specific components of the virus. In the case of coronavirus, it is a spike protein or part of it. During vaccination, this genetic information is sent to human cells. When mRNA reaches human cells, it can reproduce viral proteins and present them to the immune system, thanks to the schemes stored there. This provokes an immune response, and vaccinated people have a very low risk of eventually developing Covid-19.

However, the fact that Biontech / Pfizer’s BNT162b2 is a genetic vaccine makes some people uncomfortable. The fear that mRNA from the vaccine may alter the dormant human genome as DNA in the cell nucleus circulates in social networks. Some opponents of vaccination even use mRNA vaccination compared to plant genetic engineering.

Klaus Cichutek, director of the Paul Ehrlich Institute (PEI) responsible for vaccine safety, has already warned against “fear tactics” by vaccination opponents in this context. “The warning about genetic damage is wrong and causes unfounded fear,” Cichutek said in an interview with “Neue Osnabrücker Zeitung.” The fear that new mRNA vaccines could alter human genetics would “do not correspond to the state of scientific knowledge.”

But what is this rating based on? Summary of the most important points:

mRNA does not contact human DNA

Important point: Everything important in vaccination happens inside the cell, but it has nothing to do with the cell nucleus. However, there is only the human genome, which is conserved in the form of DNA. “MRNA is unlikely to reach DNA isolated in the (…) cell nucleus,” Carlos Guzmán, a vaccine researcher at the Helmholtz Infection Research Center, told Zeit. In the cell, the mRNA of the vaccine and the DNA of the genome are not in contact.

mRNA and DNA have different chemical structures

There is another exclusion criterion. “Integration of RNA into DNA is not possible, especially because of the different chemical structures,” PEI writes. Due to chemical differences, the two biomolecules are incompatible with each other and cannot form chains. Most important deviations: DNA is made up of double strands and RNA is made up of single strands. Both use different sugar molecules as a framework. RNA and DNA also differ in one of the four organic bases that form the “lang” of a biomolecule that looks like a ladder.

mRNA can be converted to DNA, but it’s not that easy

But couldn’t it be possible to convert mRNA to DNA and then integrate it into the genome? In fact, conversion is possible – this is done by viruses such as the AIDS pathogen HIV, which transcribes its RNA genetic material into DNA. To do this, the virus uses an enzyme called reverse transcriptase. However, it does not exist in human cells. “There is no evidence that mRNA taken up by body cells after vaccination is transcribed into DNA,” PEI writes.

mRNA is a natural component of human cells

The mRNA contained in the vaccine is not a foreign substance, but is permanently used in human cells. It is also important for the production of other proteins. As a result, some of the DNA in the cell nucleus is read and sent in the form of messenger RNA to the cell’s protein factory. Since mRNA has only a messenger function, it is quickly degraded again. It happens so quickly that it has long been questioned whether mRNA can even be used medicinally.

The virus also works with mRNA

The mRNA vaccine only mimics what the virus itself does. When Sars-CoV-2 invades a cell, its genetic information stored as RNA (coronavirus is an RNA virus) is also passed to the cell’s protein factory. Then the virus is recreated. It contains the spiked protein mentioned above and its blueprint is in the mRNA vaccine. Other viruses, such as the cold virus, use the same principle.

I already have experience with mRNA vaccines

Biontech Vaccine BNT162b2 is the first mRNA vaccine approved. However, research on the therapeutic use of mRNA has been conducted for about 30 years. In the past, mRNA vaccines have also been developed and are already being investigated in clinical studies. For example, the Tubingen-based company Curevac had previously tested an mRNA-based rabies vaccine in humans.

mRNA vaccine is better than DNA vaccine

However, some vaccines are based on DNA rather than mRNA. These are actually accidentally incorporated into the genetic makeup of human cells as “potential security risks”, as shown on the Pharmaceutical Directory Yellow List. But that’s exactly not the case with mRNA, researchers Deborah Fuller and Peter Berglund described in a June study on mRNA vaccines as “comparative advantage of mRNA (in terms of DNA vaccines).”

Conclusion: “There is no risk of mRNA being integrated into the human genome,” PEI determines. However, this does not mean that mRNA vaccines are generally risk-free. It is true that previous studies have shown that vaccines are well tolerated. According to the company, some vaccinated subjects experienced side effects such as fatigue at the injection site, headaches, joint pain, and redness. Similar reactions are known from other vaccines and are also a sign that the vaccine is doing what it is supposed to do: speed up the immune system. But what’s missing so far is information about rare and perhaps serious side effects. These are only apparent after vaccination of many people and longer observation periods.