I wrote a background piece on the mRNA vaccine recently. Since then I've come across some weird false claims about it, so I figured I'd take a minute to set things straight.
A very quick review
I won't take up a lot of time with the basics of the cellular machinery, but as you ought to know if you don't already DNA, which resides in the cellular nucleus, contains the instructions for making proteins. A "gene," basically, means the instructions for making a specific protein. Proteins are long chains of smaller chemicals called amino acids. There are 20 different amino acids encoded by DNA. (Some others occur biologically but that's a complication we can ignore for now.)
DNA consists of two strands, each consisting of a sequence of four different "bases," designated A, G, T and C. A always bonds with T, and G with C. Three letter sequences of A, G, T and C are the "words" that specify amino acids. One of the DNA strands, called the 'sense' strand, contains the codes. The other is a template that allows the DNA to reproduce when the cell divides. When it's time to make a protein, the DNA unzips to present the sense strand, and the cellular machinery makes a corresponding messenger RNA strand to carry the information out into the cell. Little cellular machines called ribosomes attach to the mRNA and move along it assembling the proteins. Once the proteins are made, the cell destroys the mRNA.
Of course, the vaccine introduces the mRNA into your cells directly, it doesn't affect your DNA at all.
So, to debunk a totally false claim that seems to be going around, mRNA does not and cannot replicate. The total amount of mRNA that's in the vaccine is the total amount that will ever be in your body, and it won't be there for long. Even if the cell tried to replicate it, which it doesn't, you'd end up with an anti-sense strand that doesn't do anything. The only permanent effect will be that the cell will display the proteins specified by the mRNA on its surface, and your immune system will make antibodies to them.
4 comments:
I'm interested in your take on the Sputnik V vaccine. Russia was criticized for rushing it some, but it seems to be extremely effective with only one dose. No one seems to be growing a third eye, either.
Report in The Lancet is very favorable. It's a more traditional adenovirus vector vaccine. That's all I know.
https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00234-8/fulltext
I'm currently in a country that has purchased the Russian vaccine along with Pfizer and a couple of others. I don't want to travel back to US until I receive one. After all the info on all of them, I'm hoping it will be Sputnik but OI really won't have a choice.
Clever cartoon explaining how the vaccine triggers immunity by using a Star Wars analogy:
https://xkcd.com/2425/
Post a Comment