In 2024, a major breakthrough in medicine was recognised with the Nobel Prize for revealing a previously unknown type of genetic switch: microRNA. This discovery, decades in the making, opens new avenues for medical breakthroughs. Here are 10 things you need to know about microRNAs.

1: What is microRNA? MicroRNA (miRNA) is a tiny, non-coding RNA molecule that regulates gene expression. Unlike mRNA, which carries instructions to make proteins, microRNA works by silencing certain genes.

2: How does it function? MicroRNA binds to specific mRNA molecules and either degrades them or prevents them from producing proteins. This fine-tunes how cells utilise genetic instructions.

FFFD45

3: A hidden regulator Scientists once believed some regions of DNA were non-functional. However, microRNA has revealed that these non-coding regions play a crucial role in regulating genes, adding complexity to our understanding of biology.

4: Role in evolution MicroRNAs have been around for hundreds of millions of years and may have contributed to the evolution of complex organisms, including humans.

5: MicroRNA and cancer Some microRNAs act as tumour suppressors by halting uncontrolled cell division, while others can encourage cancer growth by pushing cells to divide.

6: Potential in medicine Scientists are exploring microRNA-based treatments for cancer, heart diseases, and viral infections. Although none are widely available yet, they hold great promise for the future.

7: MicroRNA as biomarkers MicroRNA can assist in diagnosing diseases by acting as biomarkers, indicating specific types of cancer or other conditions a patient may have.

8: Challenges One key challenge in developing microRNA therapies is their instability, which complicates delivery within the body. Researchers are working on methods like nanoparticle delivery systems to protect and stabilise microRNA for use in treatments.

9: MicroRNA’s role in gene control MicroRNA helps explain why different cells — like muscle or brain cells — develop differently, even though they share the same DNA. By switching genes on and off, microRNAs ensure that cells perform their specific functions.

10: Unlocking the future With over 1,000 microRNAs already identified in humans, scientists are just beginning to understand their potential in medical research.

Why it matters The discovery of MicroRNA is more than a scientific curiosity; it offers new ways to treat diseases by controlling gene expression, potentially changing the future of medicine.