No mRNA Vaccines Won’t (and Can’t) Rewrite Your DNA
By: Jennifer R. Povey
Tags: Biology, Vaccines, Health, Covid 19

Photo by Markus Spiske on Unsplash

All kinds of myths and misunderstandings about the new mRNA vaccines are circulating. It’s not really a surprise. It’s new technology never used in a vaccine before, and not everyone understands it.

One of the most pervasive is that the vaccine will somehow rewrite your DNA. In the most ridiculous version it contains alien DNA that will cause your body to grow a 5G antennae so the government can read your mind.

(I’m a science fiction writer and I still can’t match this stuff).

So, let’s take a look at this technology and see if we can debunk this theory.

Photo by National Cancer Institute on Unsplash

What is mRNA?

First, let’s take a look at what mRNA actually is.

Our cells run on DNA, a highly complex molecule that’s essentially a biological code. DNA contains all the instructions needed to create the organism. It’s our master program, which we inherit from our parents and pass on to our children.

One of the things DNA does is instruct cells to make proteins. However, the DNA is all neatly tucked away in the cell’s nucleus. The ribosomes, which make proteins, need to know which ones to produce, and that varies from cell to cell.

They can’t just read the entire code, which has the instructions to produce thousands of proteins.

Enter mRNA, which stands for messenger RNA. Our cells copy off the relevant part of the DNA and send it from the nucleus to the ribosomes. The ribosomes read the mRNA and get to work making the protein.

The mRNA then goes away. It’s specifically designed to be unstable so it doesn’t stick around and confuse the ribosomes. It might last a few seconds or a few days, but it degrades and is gone.

This process is strictly one way. mRNA is created by the nucleus and sent to the ribosomes. It can’t crawl back into the nucleus and replace the DNA it was copied from.

However, mRNA that gets into a cell from outside can still tell that cell to make certain proteins. Which is

How do mRNA Vaccines Work?

That is, of course, central to how mRNA vaccines work. (It’s also part of how viruses work).

To make an mRNA vaccine you first need a genetic sequence of the virus you want to stop. You study it until you find a snippet that codes for a key protein. In the case of SARS-CoV-2, the key element is the spike that the virus uses to piece cells.

Then you wrap it in a lipid coating to prevent it from being destroyed by our blood. This is, again, the same trick viruses use. You design it to enter immune cells and trick them into creating the spike protein.

Your immune system then recognizes this protein as foreign and creates antibodies and T cells against it.

Meanwhile, the mRNA itself, as it’s designed to do, disappears.

Photo by National Cancer Institute on Unsplash

Are We Sure it Can’t Change Our DNA?

Yes! Because our bodies already have safeguards to keep mRNA from wandering into the nucleus and messing with our DNA. The synthetic mRNA in the vaccine is also kept out by the same safeguards.

One good way to think of it is that our DNA is a read only disc, like an old CD.

You can rip a track off of the CD and put it on your hard drive, but you can’t then replace the track with another one. Except then the ripped track self destructs after you’ve listened to it.

So no, the mRNA vaccines can’t change your DNA. I can see where people got there from “It gives your body instructions to make the spike protein.”

But it’s more like a very harmless mini-virus that’s showing the threat to your immune system so it can recognize the real thing.

This vaccine technology is going to come up a lot more in the future. mRNA flu vaccines, for example, would take lot less time to make. This would allow us to make a better guess as to which strains to include in the vaccine in a given year.

Oh, and while I’m here, no, it can’t give you COVID-19 (it only has the spike protein code).

It also won’t make you infertile. I’ll address that one in another post.