Do vaccines really change our DNA?

One common fear about vaccinations is the fear that the vaccine will change our DNA or the DNA of future offspring, increasing the risk of developing cancer and autoimmune diseases. We decided to test whether modern vaccines are capable of changing the genetic code.

Stories like this are spreading on social media. networks and messengers. Their authors claim: “Such vaccines were previously banned for use on humans because they interfere with the human gene pool. With this vaccine, foreign DNA will be placed directly into the nucleus of the cell, which by definition is genetic modification. The COVID-19 vaccine is a gene therapy. It will change your DNA and turn you into a GMO. Exactly how this will affect our genes has not been disclosed, but I assure you it will affect us in the most terrible way." Active theory about genetic modification of humans after vaccination distributes also Doctor of Medical Sciences Pavel Vorobyov: “We introduce RNA, we have a reverse transcriptase mechanism that reads the RNA and converts it into DNA. This is how the structure of the human genome changes, we don’t know anything about it.”.

Most ancient The method of vaccination is inoculation and variolation against smallpox. A healthy person had to inhale the crushed scabs of the sick person or inject subcutaneously liquid from the blisters of the sick person. The method was controversial and even prohibited in some countries, since it did not provide a sufficiently reliable guarantee, and could also provoke epidemics.

In the 1880s, French chemist and microbiologist Louis Pasteur invented vaccines against chicken cholera, rabies and anthrax, using weakened microorganisms in them. Vaccines made in this way are now called live vaccines. There are live vaccines for the prevention of plague, anthrax, tularemia, brucellosis, influenza, rabies, mumps, smallpox, yellow fever, measles, polio, tuberculosis.

To another class include inactivated (killed) vaccines. These are vaccines against polio, influenza, typhus, cholera, plague, whooping cough, and hemophilus influenzae. Some diseases (diphtheria, tetanus) are prevented by a third type of vaccine - toxoids (weakened toxins of microorganisms). Also exist subunit (containing not the whole virus or bacterium, but only parts of it), vector vaccines (using safe virus transport and elements of the corresponding pathogen) and vaccines based on genetic material (delivering messenger RNA or DNA - “instructions” - to the body for the synthesis of the desired specific protein).

Of course, neither a living microorganism nor a dead one, much less the toxin it produces, can change the DNA can't. Subunit vaccines contain proteins or sugars, and vector vaccines contain an altered adenovirus shell consisting of proteins that is incapable of reproduction. In particular, coronavirus vaccines contain an adenovirus-linked gene encoding the S-protein, which is responsible for the penetration of the virus into the cell. Exists several already approved vector vaccines against coronavirus, for example, the Russian Sputnik V, the Anglo-Swedish AstraZeneca, the American Johnson & Johnson; clinical trials for others are still underway. Unlike the AstraZeneca drug, the Russian vaccine contains two different adenoviral vectors. None of these vaccines are capable of altering DNA. “The human genome can be influenced by something that can integrate into the human genome or somehow influence the DNA structure. If a drug does not multiply in the human body, then it cannot integrate and interact with our nucleic acid,” explains microbiologist, director of NICEM named after. N. F. Gamaleya Alexander Ginzburg. At the same time there is researchthat the adenoviral vector can be integrated into DNA during insertional mutagenesis, but the frequency of this phenomenon is lower than the occurrence of random mutations. Vector vaccines have been used for many years and help protect humanity - for example, from the Ebola virus. Vector vaccine against it was registered in 2015 in Russia, and in 2019 - in USA.

The idea of ​​constructing a vaccine based on messenger RNA (aka mRNA) and DNA is also not new. First publications include to the 50–60s of the last century, when scientists proved that the genetic information of DNA retains the ability to be written and read after being transferred to another cell. But then things didn’t go further than theory. The first vaccine based on mRNA technology was registered only in December 2020. It was the Pfizer-BioNTech vaccine against the new coronavirus.

In their action they are one step ahead others - the vector delivers the virus, it is unpacked, the cells read it and begin to produce antigen proteins, and the mRNA immediately supplies the “recipe” for these antigen proteins. Messenger RNA is not integrated into the body of the vaccinated person. First of all, she too much fragile, destroyed after the transfer of the “recipe” and eliminated from the body in an average of 72 hours. Secondly, mRNA is not hits into the nucleus of the cell - the part where DNA is stored, since the shell of the nucleus allows large molecules only to leave it, and not to enter. Therefore, mRNA does not interact with DNA. 

However, there are still exceptions: with the help of the reverse transcriptase gene - a special enzyme - RNA can turn into DNA and gain access to the nucleus. A non-peer-reviewed preprint of such a study was published December 2020. Virologist, Nobel laureate and discoverer of the reverse transcriptase gene David Baltimore in an interview with Science magazine agreed with this possibility, stipulating that fragments of the SARS-CoV-2 virus do not lead to the formation of infectious material and thus represent a biological dead end.

Vaccination with DNA vaccines is also called genetic immunization. To date, six veterinary DNA vaccines have been approved: melanoma in dogs, for incentive production of growth hormone in pigs, against infectious necrosis hematopoietic tissue in salmonids, against pneumonia in mice, against fever West Nile in horses and sei whales (species of cetaceans). No vaccine has yet been approved for humans. Underway clinical trials of vaccines against hepatitis C, cervical cancer, head and neck cancer, dental caries, HIV, influenza and leukemia. Also started a study of a DNA vaccine against coronavirus, currently involving 120 people. However, such vaccines will not be able to change human DNA, since foreign DNA, although it penetrates the cell nucleus, usually does not enter it built in. In theory, this can happen extremely rarely, however, note scientists, the probability of this will be three orders of magnitude lower than that of spontaneous mutations, which makes such a risk, according to them, insignificant. To date, such cases not recorded.

Thus, neither live, nor killed, nor vector vaccines currently used are integrated into the cell nucleus at all. Messenger RNA in very rare cases can penetrate the nucleus, but is not able to integrate into it and begin to reproduce in cells formed as a result of division. DNA vaccines have the potential to be integrated into the genome, but so far no such cases have been recorded and mass vaccination of people with such vaccines is not carried out.

Updated August 27, 2021. The first DNA vaccine against coronavirus was approved for emergency use on August 20 in India. It's called ZyCov-D and is recommended for use by people over 12 years of age. Three doses are required to obtain full immunity. In addition to the innovative design of the vaccine, the method of its administration is also interesting - a skin patch with microneedles. However, for this vaccine, the risk of integration into DNA is three orders of magnitude lower than the risk of random mutations.

Not true

What do our verdicts mean?

Read on the topic:

1. Professor Sparrowec and misinformation about the Sputnik V vaccine
2. New DNA vaccine stops cancer
3. How to fix human DNA?