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mRNA Vaccines

How mRNA vaccines work ?

Understanding COVID-19 mRNA Vaccines

Can COVID-19 vaccines alter my DNA ?

No, COVID-19 vaccines do not alter your DNA.

The Pfizer/BioNTech COVID-19 vaccine uses a fragment of messenger RNA (mRNA) to instruct your body to make an immune response against COVID-19. There is a crucial difference between mRNA and DNA. 

DNA, which makes up our genetic code, is larger, double stranded and very long. The mRNA is a single stranded copy of a small part of the DNA, which is often released to send instructions to other parts of the cell. 

DNA is stored in the protected centre of our cells – the nucleus. The mRNA is broken down quickly by the body. It never enters the nucleus, and cannot affect or combine with our DNA in any way to change our genetic code. 

Instead, COVID-19 mRNA vaccines teach the cell how to make a protein that triggers an immune response specific to COVID-19. The vaccines work with the body’s natural defences to develop immunity to disease.

Australian Government Department of Health


EXPERT REACTION: Can mRNA from COVID-19 vaccines be integrated into human DNA ?

Professor Nigel McMillan (Director in Infectious Diseases and Immunology at Menzies Health Institute Queensland, Griffith University) : « We know the certain viruses such as HIV are able to insert their RNA into the human genome but only after they have converted it into DNA.  This is accomplished via a virus enzyme called reverse transcriptase – an enzyme humans don’t have. So, the upshot is we don’t have a way for mRNA vaccines to be inserted into our genomes. So, current vaccines are safe.  However, there was a recent very controversial paper in the Proceedings of the National Academy of Science [PNAS] claiming this was possible.  The scientific consensus is that this work is preliminary, not proven, and likely an artifact of the experimental process rather than a real finding.  The claims have not been replicated by other researchers at this stage (Scimex – 18/06/2021).