The 2024 Nobel Prize in Physiology or Medicine has been awarded to American scientists Victor Ambros and Gary Ruvkun for their pioneering research on microRNAs—tiny molecules that play a major role in gene regulation.
Their work significantly advances our understanding of the origins of complex life on Earth and the diversity of human tissues.
MicroRNAs affect how genes, the fundamental blueprints for life, are expressed in living organisms. Although every human cell contains the same basic genetic information, stored in DNA, the cells vary greatly in appearance and function. For instance, heart cells beat rhythmically, nerve cells transmit electrical impulses, and liver cells carry out essential metabolic functions.
Similarly, light-sensitive cells in the retina perform entirely different roles from white blood cells that produce antibodies to fight infection. Such diversity is possible because genes are expressed differently across various cell types, a process in which microRNAs are deeply involved.
Ambros and Ruvkun were the first scientists in the United States to identify microRNAs and uncover how they control gene expression across various organs. The Nobel Assembly at Sweden’s Karolinska Institute stated that their “revolutionary finding unveiled an entirely new concept of gene regulation, which proved to be crucial for multicellular organisms, including humans.”
Currently, scientists estimate that the human genome encodes over 1,000 different microRNAs. Without the regulatory power of these molecules, all cells within an organism would be identical, meaning microRNAs played a vital role in the evolution of complex life forms.
Disruptions in microRNA regulation have been linked to various diseases, including cancers, congenital disabilities, and hearing loss. One notable example is DICER1 syndrome, which results from mutations affecting microRNAs and can lead to cancer in multiple tissues.
“The prize carries a monetary reward of 11 million Swedish kronor (£810,000), shared by the winners”.