The Nobel Prize in Medicine was awarded on Monday to two American scientists for their discovery of microRNA, a previously unknown type of genetic switch that they hope could pave the way to new medical breakthroughs.
But while many treatments and trials are being developed using microRNAs against cancer, heart disease, viruses and other diseases, none have actually reached patients yet.
And when new Nobel laureates Victor Ambrose and Gary Ruvkun revealed their discovery decades ago, the world paid little attention, thinking it was just “something weird about insects,” says Eric Miska, a geneticist at the University of Cambridge. Told AFP.
Here’s an explanation of how these little genetic switches actually work inside our bodies.
-What is microRNA? ,
Every cell in the human body has the same set of instructions, called DNA. Some turn into brain cells, while others become muscles.
So how do cells know what to become? The relevant part of the DNA’s instructions is indicated through a process called gene regulation.
Ribonucleic acid (RNA) normally functions as a messenger. It carries instructions from DNA to proteins, which are the building blocks of life that turn cells into brains or muscles.
Miska cited the example of messenger RNA vaccines introduced against COVID-19 during the pandemic, which insert a message with new instructions for building a protein that blocks the virus.
But two new Nobel laureates, Ambrose and Ruvkun, discovered an entirely new type of gene regulator that science had previously ignored.
Rather than being a messenger that transmits information, the microRNA acts as a switch to turn other genes off and on.
“This was a whole new level of control that we completely missed,” said Miska, who has worked on microRNAs for two decades, including on new Nobel laureates.
“The discovery of microRNAs brought an additional level of complexity by revealing that regions that were thought to be non-coding play a role in gene regulation,” French researcher Benoit Ballester told AFP.
– What did the Nobel winners do? ,
In the 1980s, Ambrose and Ruvkun were working separately on how genes interact in a millimeter-long roundworm called C. elegans.
When they compared their work, it led to the discovery of microRNAs. Ambrose disclosed this discovery in a 1993 paper.
“Nobody really paid much attention,” Miska said, explaining that most scientists at the time thought it applied only to insects.
Then in 2000, Ruvkun published research showing that microRNAs are present throughout the animal kingdom, including humans and even some viruses.
“It’s not a strange thing that insects do, but in fact all animals and plants are completely dependent on them for growth and normal function,” Miska said.
More than a thousand genes that respond to microRNAs are now believed to exist in the human body.
– How can it help us? ,
There are several new treatments and tests using microRNAs that are undergoing testing but none have been made widely available.
“Although microRNAs do not have any very obvious applications yet, understanding them, knowing that they exist, understanding their counter-regulatory networks is always the first step,” Gunilla Carlsson Hedestam of Karolinska Institutet told reporters in Stockholm.
MicroRNAs are particularly promising for fighting cancer because some of these switches “act as tumor suppressors, so they put the brakes on cells that divide inappropriately,” Miska said.
Others, meanwhile, “induce cells to divide, which can lead to cancer”, he said.
Because many viruses use microRNAs, several antiviral drugs are in various stages of development, including for hepatitis C.
A complicating factor is that microRNAs can be unstable.
But scientists also hope they could be used as a test, called a “biomarker,” that could tell what type of cancer a patient might be suffering from, for example.
– What next? ,
It’s also possible that microRNAs may be involved in the evolution of our species, Miska said.
“It seems that microRNAs play an important role in why the human brain is different from the brains of other primates,” Miska said.
While the human brain is difficult to study, Miska hoped that future research would reveal more.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
