Skip to content
Nobel Jews
Portrait of Gary Ruvkun
Photo: Arthur Petron, Own work · CC BY-SA 4.0 via Wikimedia Commons

Nobel Prize in Physiology or Medicine · 2024

Gary Ruvkun

He helped discover microRNAs, tiny RNA switches that fine-tune our genes, and showed that humans share them with worms.

The Nobel citation: “for the discovery of microRNA and its role in post-transcriptional gene regulation”
Born
1952, Berkeley, CA, USA
Shared with
Victor Ambros
Affiliation at the time
Massachusetts General Hospital, USA; Harvard Medical School, USA

Medicine prize

2024

Shared with 1 other laureate.

Age that year

72years

Born in 1952.

Sources cited

21

Fact-checked September 24, 2026.

  • His grandparents were Yiddish-speaking Jewish immigrants from the Russian Empire. His father's parents ran a junkyard in Stockton, California.
  • After college he lived in his van for a year while planting trees in Oregon, then travelled through Latin America before starting graduate school.
  • In 2000 his lab found that a tiny worm RNA called let-7 also exists in flies, fish and humans, which turned a worm curiosity into a new field.
  • Massachusetts General Hospital says microRNA research has grown from his and Victor Ambros's two 1993 papers to about 176,000 papers.
  • He has co-led a NASA-funded project to adapt DNA-sequencing tools to search for life on Mars and other worlds.

The breakthrough

Discovering microRNA, a hidden layer of gene control

Every cell in your body carries the same genes, yet a muscle cell and a nerve cell are very different. The difference comes from gene regulation: each cell switches on only the instructions it needs. Until 1993, scientists thought proteins did almost all of that switching.

Ruvkun and Victor Ambros studied a worm 1 millimetre long, C. elegans, and two genes that control the timing of its growth. One gene, lin-4, was known to shut down another, lin-14. Ambros found that lin-4 does not make a protein at all. It makes a tiny RNA only 22 letters long. Ruvkun showed that lin-4 does not stop lin-14's message from being made. It blocks the message from being turned into protein, by acting on a stretch at the message's tail end. When the two compared their sequences in June 1992, the tiny RNA partly matched several spots in that stretch, like pieces of a zipper. It sticks to the message and jams it.

Think of a recipe card being carried to the kitchen. The microRNA is a sticky note slapped on the card that says 'don't cook this yet.'

For seven years the finding looked like a worm oddity. Then, in 2000, Ruvkun's lab found a second such RNA, let-7, and showed that the same molecule exists in flies, fish and humans. Scientists have since found more than a thousand microRNA genes in the human genome.[2],[3],[7],[8],[9]

“We weren’t thinking that this is going to win a Nobel Prize, we were thinking this is really interesting.”
Gary Ruvkun, Telephone interview with Nobel Prize Outreach minutes after the 2024 announcement, on how he and Victor Ambros saw their discovery in 1993.[4]

What it meant for humanity

MicroRNAs changed how biologists understand life. Before 1993, gene control was pictured as proteins sitting on DNA and flipping switches. Ruvkun and Ambros showed there is a second control layer, made of tiny RNAs, that works after a gene's message has been made. The Nobel committee calls it essential for complex, many-celled life. Later studies estimated that more than 60 percent of human protein-coding genes have been shaped by evolution to keep their microRNA binding sites.

The discovery also explains some disease. Faulty microRNAs, or faults in the machinery that makes them, are linked to cancer, to inherited hearing loss, to eye and skeletal disorders, and to DICER1 syndrome, a rare condition that causes tumours in children. Doctors and researchers now study microRNA levels as possible warning signs of disease.

Medicines built on microRNAs are still mostly promise. One encouraging early result came in 2013. In a small trial, a drug that blocked a liver microRNA, miR-122, sharply cut hepatitis C virus levels. Ruvkun's hospital says microRNA-based treatments are in clinical trials for heart disease, cancer and brain diseases. As of 2024, no microRNA drug had won approval from the US Food and Drug Administration.

Ruvkun's lab has also mapped how an insulin-like signal controls fat storage and lifespan in worms. The same pathway exists in people, where related genes may go wrong in diabetes. His career is a strong case for curiosity-driven research: a question about worm timing opened a field that now fills about 176,000 papers.

  • Research on microRNAs grew from the two 1993 papers by Ruvkun and Ambros to about 176,000 papers by 2024, according to Massachusetts General Hospital.[11]
  • A 2009 study estimated that more than 60 percent of human protein-coding genes have been under evolutionary pressure to keep pairing with microRNAs.[12]
  • Faulty microRNA regulation is linked to cancer, inherited hearing loss, eye and skeletal disorders, and DICER1 syndrome, a rare childhood tumour condition.[2],[3]
  • In a 2013 trial of 36 hepatitis C patients, miravirsen, a drug that blocks the liver microRNA miR-122, cut virus levels in a dose-dependent way, and the effect outlasted the treatment.[13]
  • In 1997 his lab showed that DAF-16, a gene switch, carries insulin-like signals that control fat storage and lifespan in worms, and suggested that related human genes may be involved in diabetes.[10]

Impact in numbers

Ruvkun's impact is mostly on knowledge, and that knowledge is large. With Ambros he found a new layer of gene control. With let-7 he showed it is ancient and shared by humans, which turned a worm oddity into one of the busiest fields in biology. MicroRNAs now help explain development, cancer and several inherited diseases, and they are studied as markers of disease and as drug targets. The same discovery fed into the wider small-RNA revolution that also includes RNA interference. Honest accounting, though, gives no reliable count of lives saved or people treated. No microRNA medicine had been approved by 2024, and the approved RNA-silencing drugs trace mainly to other scientists. For that reason this profile makes no numeric impact claim. His real gift is a better map of how living things work, which future medicines will draw on.

Fundamental scienceHealth

No number is given here on purpose. Some contributions cannot be counted honestly, and we would rather describe them than invent a figure.

The double edge

No harms from Ruvkun's own research are documented. The medical field it opened has had setbacks. The first microRNA cancer drug tested in people, MRX34, was stopped early after serious immune reactions, and four patients died. A 2024 review found that no microRNA drug had reached a final-stage trial or won US approval, and several programmes had ended over toxicity. The early excitement about microRNA medicines has so far run ahead of the results.

  • Moderate

    First microRNA cancer drug trial halted after patient deaths

    MRX34, a copy of the microRNA miR-34a packed in fat bubbles, was the first microRNA-based cancer therapy tested in people. Among 85 patients with advanced tumours, three responded partly, but the trial closed early because of serious immune-related side effects that led to four deaths. The drug was developed by a company, Mirna Therapeutics, not by Ruvkun.[14]

  • Minor

    Promised microRNA medicines have been slow to arrive

    A 2024 review found that no microRNA therapy had reached a phase III trial or won FDA approval, and that several had been stopped over toxicity. Getting the drugs to the right tissue and avoiding side effects remain unsolved problems.[15]

Against the odds

Ruvkun's story is one of immigrant families who got a foothold in America, not of personal persecution. His four grandparents came from the Russian Empire. They were part of a huge wave: between 1881 and 1924, more than two and a half million Jews from Eastern Europe came to the United States, pushed out by persecution and poverty. Pogroms, violent attacks on Jews, had swept the empire's southern and western provinces in 1881 to 1884. His mother's parents came into North America through Winnipeg around 1905. Family lore says his grandfather misspelled the family name on census forms, perhaps out of fear of being deported.

The door closed soon after. US laws in 1921 and 1924 set quotas that sharply cut immigration from Eastern Europe. In the same years Columbia, Harvard and Yale began limiting how many Jewish students they admitted. Ruvkun's father enrolled at the public University of California, Berkeley, in 1937, where tuition was about 50 dollars a year. He became an engineer who built steel mills and cement plants across Latin America.

Ruvkun says he never heard family stories of antisemitism in Stockton, where his grandfather was respected for his honesty. He grew up in the Bay Area as an engineer's son, and he followed his father to Berkeley. He later earned his doctorate at Harvard, one of the universities that had once rationed places for Jewish students.

  • 1905

    Other

    His Yiddish-speaking grandparents on both sides left the Russian Empire during the era of pogroms and mass Jewish emigration. His mother's parents entered North America through Winnipeg around 1905; he has said he does not know how they made the journey.[5],[18],[19]

  • 1924

    Discrimination

    In his parents' generation, US immigration quotas in 1921 and 1924 cut off most Jewish immigration from Eastern Europe, and Harvard, Columbia and Yale limited Jewish admissions. His father studied at the public University of California, Berkeley.[5],[19],[20],[21]

Jewish background

Both parents JewishCulturally Jewish

Ruvkun was born in Berkeley, California, to Samuel and Dora (née Gurevich) Ruvkun. All four of his grandparents were Jewish immigrants from the Russian Empire; he believes both couples spoke Yiddish at home. His father's parents ran a junkyard in Stockton, and his mother's parents settled in Seattle after entering through Canada around 1905. His mother and her sister later lived in a residence for young Jewish women in San Francisco. In a 2025 Nobel interview he described his family as Russian Jewish. The sources used here say nothing about religious practice.[5],[17]

Key dates

  1. 1952

    Born in Berkeley, California, to a family whose grandparents were Yiddish-speaking Jewish immigrants from the Russian Empire.[1],[5]

  2. 1973

    Graduates from the University of California, Berkeley, with a degree in biophysics. He then plants trees in Oregon for a year and travels through Latin America.[4],[5],[11]

  3. 1976

    Moves to Boston to start graduate school at Harvard University.[5]

  4. 1982

    Earns his PhD at Harvard and begins postdoctoral work split between the labs of Walter Gilbert and Robert Horvitz, where he and Victor Ambros study worm timing genes.[2],[3]

  5. 1985

    Opens his own lab at Massachusetts General Hospital and Harvard Medical School.[2]

  6. June 11, 1992

    Swaps sequence data with Ambros one evening, and both see that the tiny lin-4 RNA matches the tail end of the lin-14 gene's message.[3]

  7. December 1993

    Publishes, back to back with Ambros in the journal Cell, the first description of gene control by a microRNA.[2],[7]

  8. October 1997

    His lab shows that the gene switch DAF-16 carries insulin-like signals that control fat storage and lifespan in worms.[10]

  9. 2000

    Discovers let-7, the second microRNA, and shows it exists across the animal kingdom, including in humans.[6],[8],[9]

  10. 2008

    Shares the Lasker Award for Basic Medical Research with Ambros and David Baulcombe.[11]

  11. September 2020

    Co-authors tests on parabolic flights showing that a pocket-sized DNA sequencer works at gravity levels like those on Mars, the Moon and Europa, part of a search for life beyond Earth.[16]

  12. October 7, 2024

    Awarded the Nobel Prize in Physiology or Medicine, shared with Victor Ambros, for the discovery of microRNA.[1],[2]

Sources

  1. 1.Gary Ruvkun – Facts – 2024 · NobelPrize.org (Nobel Prize Outreach), 2024
  2. 2.Press release: The Nobel Prize in Physiology or Medicine 2024 · The Nobel Assembly at Karolinska Institutet (NobelPrize.org), 2024
  3. 3.Scientific background: For the discovery of microRNA and its role in post-transcriptional gene regulation · The Nobel Committee for Physiology or Medicine (NobelPrize.org), 2024
  4. 4.Gary Ruvkun – Interview (telephone interview, October 2024) · NobelPrize.org (Nobel Prize Outreach), 2024
  5. 5.Gary Ruvkun – Nobel Prize Conversations podcast (transcript) · NobelPrize.org (Nobel Prize Outreach), 2025
  6. 6.Gary Ruvkun – Banquet speech · NobelPrize.org (Nobel Prize Outreach), 2024
  7. 7.Posttranscriptional regulation of the heterochronic gene lin-14 by lin-4 mediates temporal pattern formation in C. elegans (Wightman, Ha, Ruvkun), Cell 75(5):855-862 · Cell (via PubMed), 1993
  8. 8.The 21-nucleotide let-7 RNA regulates developmental timing in Caenorhabditis elegans (Reinhart et al.), Nature 403:901-906 · Nature (via PubMed), 2000
  9. 9.Conservation of the sequence and temporal expression of let-7 heterochronic regulatory RNA (Pasquinelli et al.), Nature 408:86-89 · Nature (via PubMed), 2000
  10. 10.The Fork head transcription factor DAF-16 transduces insulin-like metabolic and longevity signals in C. elegans (Ogg et al.), Nature 389:994-999 · Nature (via PubMed), 1997
  11. 11.Mass General Hospital Researcher Gary Ruvkun Honored with 2024 Nobel Prize (Wayback Machine snapshot) · Massachusetts General Hospital, 2024
  12. 12.Most mammalian mRNAs are conserved targets of microRNAs (Friedman, Farh, Burge, Bartel), Genome Research 19(1):92-105 · Genome Research (via PubMed), 2009
  13. 13.Treatment of HCV infection by targeting microRNA (Janssen et al.), N Engl J Med 368:1685-1694 · New England Journal of Medicine (via PubMed), 2013
  14. 14.Phase 1 study of MRX34, a liposomal miR-34a mimic, in patients with advanced solid tumours (Hong et al.), Br J Cancer 122:1630-1637 · British Journal of Cancer (via PubMed), 2020
  15. 15.Trials and Tribulations of MicroRNA Therapeutics (Seyhan AA), Int J Mol Sci 25(3):1469 · International Journal of Molecular Sciences (via PubMed), 2024
  16. 16.Nanopore sequencing at Mars, Europa, and microgravity conditions (Carr et al.), NPJ Microgravity 6:24 · npj Microgravity (via PubMed), 2020
  17. 17.Gary Ruvkun · Wikipedia
  18. 18.Pogroms (Holocaust Encyclopedia) · United States Holocaust Memorial Museum
  19. 19.A Century of Immigration, 1820-1924 (From Haven to Home: 350 Years of Jewish Life in America) · Library of Congress
  20. 20.The Immigration Act of 1924 (The Johnson-Reed Act), Milestones in the History of U.S. Foreign Relations · Office of the Historian, US Department of State
  21. 21.How the Ivy League's Jewish quotas shaped higher education (interview with Mark Oppenheimer) · Inside Higher Ed, 2022

Fact-checked on September 24, 2026 by a separate AI fact-checking pass that re-opened the sources, with 6 corrections made. How we check

Suggest a correction