Genetics Unzipped, the podcast from the Genetics Society, is back for 2021 with a new series of stories from the world of genes, genomes and DNA. In the first episode, presenter Kat Arney takes a look at the story behind the discovery of messenger RNA (mRNA) and finds out how mRNA has been pressed into service as a COVID-19 vaccine at breakneck speed.
The 1950s and 60s was the ‘golden age’ of molecular biology, as scientists unravelled the structure of DNA, cracked the genetic code and got to grips with the machinery of life inside cells. But while researchers had figured out that DNA was the genetic code that instructed cells how to build proteins, the connection between the two was a mystery.
The missing link turned out to be messenger RNA, or mRNA – a molecular ‘tape recording’ copied from DNA, which is ‘replayed’ by ribosomes to make proteins. There were some big names involved in the story of mRNA, including Francis Crick, Sydney Brenner and Francois Jacob and more, but pinning down who actually discovered this vital molecular messenger is tricky. So tricky, in fact, that nobody was ever awarded a Nobel Prize for it, despite being such a fundamental discovery.
As scientist and author Matthew Cobb explains in his article delving into the history of mRNA: “Who discovered mRNA?” It is complicated. No wonder the Nobel Prize committee did not try and reward the discovery.
“Naming just three (or even six) people would be invidious — mRNA was the product of years of work by a community of researchers, gathering different kinds of evidence to solve a problem that now looks obvious, but at the time was extremely difficult. But that is the nature of history — it straightens out what at the time was tangled and unclear.”
Moving from the 1960s right up to the present day, Kat then explores the science behind mRNA vaccines for COVID-19, finding out how they work, why they were developed so fast for COVID-19, and how this new technology might change the face of immunisation and public health in the future.
Perhaps the key breakthrough in the development of mRNA vaccine technology came Hungarian researcher Katalin Karikó, who together with her colleague Drew Weissman at the University of Pennsylvania found the solution to the problem of mRNA triggering harmful immune reactions instead of helpful protective ones.
Rather than using exactly the same four bases normally found in mRNA inside cells – adenine, cytosine, guanine and uracil – they swapped out some of them for slightly modified versions, which could still be read in the same way by ribosomes to make proteins but didn’t set off an unwanted excessive immune response.
Published in 2005, their discovery transformed the previously languishing field of mRNA therapeutics into a game-changing medical technology, catching the eye of scientists who would eventually become the founders of the two leading COVID mRNA vaccine companies – BioNTech and Moderna.
mRNA COVID-19 vaccines from Pfizer/BioNTech and Moderna have now been authorised for use in the UK and US and are also being rolled out in a number of other countries. Although it’s going to take a while to vaccinate everyone – and even longer to get the whole world vaccinated – it looks like there might be light at the end of the tunnel.
Listen to the whole story and find show notes and a full transcript at GeneticsUnzipped.com.
Genetics Unzipped is the podcast from the UK Genetics Society, presented by award-winning science communicator Dr Kat Arney and produced by First Create the Media. Follow Genetics Unzipped on Twitter @geneticsunzip, and the Genetics Society at @GenSocUK