From the proof that DNA carries hereditary information to the Human Genome Project: Science revisits discoveries that changed the life sciences, but whose discoverers did not win a Nobel Prize for these achievements.
More in the pre-Nobel article series: Physics — Five Breakthroughs That Changed Science and Didn't Win a Prize | Chemistry — Three Breakthroughs Still Awaiting a Prize
On Monday, October 5, 2026, the Nobel Prize announcement week will begin with the announcement of the winners in physiology or medicine. According to the official schedule, the announcement will take place at 12:30 Israel time at the earliest. After that, the winners in physics, chemistry, literature and peace will be announced, and on October 12, the sequence will end with the announcement of the Prize in Economic Sciences in Memory of Alfred Nobel.
In preparation for the event, he published Science article by journalist Ailie McWhinnie, which reviews six breakthroughs in biology that were not recognized by the Nobel Prize in Physiology or Medicine. This is not an official list of candidates or a prediction of this year's winners, but rather a look at the gap between the importance of a discovery and the possibility of awarding the prize.
Sometimes scientific recognition comes late. Sometimes the achievement grows from the work of many researchers, while one scientific prize can be shared by at most three people. And sometimes the researchers die before the committee has time to recognize their work. The possible explanations presented in the Science article are based on historians and researchers; they should not be presented as official reasons for the Nobel Committee's decisions.
1. Identification of DNA as the hereditary material: Before the double helix
The 1962 Nobel Prize in Physiology or Medicine was awarded to James Watson, Francis Crick, and Maurice Wilkins for their work on the molecular structure of nucleic acids and their significance for the transmission of information. But a more fundamental question had been answered earlier: Which molecule carries the traits that are passed down from generation to generation?
At the beginning of the 20th century, it was known that chromosomes contained DNA and proteins. Proteins, made up of a wide variety of amino acids, seemed to have a more appropriate complexity for carrying hereditary information. DNA, made up of four types of building blocks, seemed to many to be too simple.
Oswald Avery, Colin MacLeod, and McLean McCarthy were studying pneumococcus bacteria at the Rockefeller Institute. They sought to identify a substance that transferred a trait from one type of bacteria to another. The method was to break down various components in the bacterial extract and test whether the ability to transfer was preserved. Breaking down the proteins or RNA did not eliminate it; breaking down the DNA did. In their 1944 paper, they presented evidence that the substance causing the change was DNA.
The importance was the transition from identifying a hereditary trait to identifying its chemical basis. Only later was evidence added from other systems and it became clear how the structure of DNA allows information to be stored and copied. Avery was nominated for the Nobel Prize, but skepticism about his conclusions did not immediately disappear. He died in 1955, without winning. Science also mentions hypotheses regarding his reclusive nature, but these cannot be seen as a proven explanation for the committee's decision.
2. Brenda Milner: You can learn without remembering that you learned.
Brenda Milner's research has shown that memory is not a single capacity located in one place in the brain. One of the most crucial pieces of evidence came from the patient Henry Molaison, known for decades by the initials HM. After surgery for epilepsy, which involved removing tissue from the medial temporal lobes, including parts of the hippocampus, his ability to form new memories of events was severely impaired.
Milner systematically studied him and discovered a surprising observation: his performance on a drawing task improved with training, even though he had no memory of the training sessions themselves. That is, the brain was able to acquire a new skill without retaining a conscious memory of its acquisition.
The distinction between memory of events and the learning of skills was fundamental to understanding memory systems. It also illustrated how brain function could be learned from comparing impaired and preserved abilities. Milner and her colleagues later combined neuropsychological questions with brain imaging technologies, including PET, to link brain activity to behavior.
Milner won the 2014 Qualey Prize in Neuroscience with John O’Keefe and Marcus Reichel. That same year, O’Keefe also won the Nobel Prize, with May-Britt and Edvard Moser, for discovering components of the brain’s positioning system. Milner’s own memory research went without a Nobel. Science notes that she celebrated her 108th birthday this year; it offers no official reason for her not being selected.
3. The discovery of stem cells: proof that a single cell can establish a population
The concept of stem cells was well-known even before it was possible to experimentally prove the existence of such cells. The question was how to show that a population of different types of blood cells arose from a common source, and that this source was also capable of renewal.
James Till and Ernest McCulloch at the Ontario Institute for Cancer Research used a system of transplanting bone marrow cells into irradiated mice. Colonies of cells developed in the spleen. In a study with Andy Becker, published in 1963, chromosomal changes were used as markers to identify cells of common origin: different types of cells in the same colony bore the same marker, evidence that they originated from a single cell.
Further transplantation experiments have also examined the ability to regenerate. The two properties together—the creation of specialized cells and self-renewal—have turned the hair stem cell into a subject of experimental research. Hematopoietic stem cells are not capable of becoming any cell in the body; their importance is in the production and regeneration of the blood system.
Science notes that the later work of Donald Metcalfe and Leo Sachs on cell culture was also crucial to the development of the field. The large number of key researchers is one possible reason that observers suggest for the difficulty of awarding a prize limited to three winners. This is speculation, not an explained decision by the committee.
The 2012 Nobel Prize in Medicine was awarded to John Gurdon and Shinya Yamanaka for reprogramming adult cells. This is a breakthrough related to stem cells, but it is not the same as proving the existence of stem cells in the blood system.
4. Tony Pawson: How an outside signal organizes a response inside the cell
Cells respond to hormones, growth factors, and messages from their environment. The binding of a signaling molecule to a receptor is not the end of the story: it needs to be translated into actions within the cell, such as changing gene expression or initiating division.
Tony Foson studied how proteins are arranged in signal transduction pathways. He identified the importance of protein segments called SH2. These segments recognize a tyrosine to which a phosphate group has been attached, in the context of a suitable protein sequence. Thus, phosphorylation of a receptor or other protein creates a docking site that recruits other proteins to it.
The principle explains how a brief encounter on the cell surface can assemble an array of proteins that executes a coordinated response. The proteins do not need to be in a fixed assembly beforehand: the signal itself creates the conditions for their assembly. Altering this mechanism could disrupt the control of cell behavior.
Foson's work helped to understand pathways that are disrupted in diseases including cancer, and contributed to the scientific basis for research into therapies that target signaling pathways. He was considered a possible Nobel candidate and won other prizes, but died in 2013 at the age of 60. The hypothesis that he would have won if he had lived longer is unproven.
5. Ben Barres: Glial cells are active partners in shaping the brain
For years, nerve cells have received most of the attention in brain research. Glial cells have been seen primarily as a support system. Ben Barres has helped change that picture by developing ways to isolate different types of brain cells and study their functions.
His group's research has shown that star-like cells called astrocytes secrete factors that promote the formation of synapses—the points of contact through which nerve cells communicate. Other work has also linked glial cells to the elimination of connections, a process essential for shaping neural networks during development.
This suggests that the number and organization of connections in the brain are not determined solely by neurons. Astrocytes and microglia participate in the construction and design of the network. This is an expansion of the unit that must be studied to understand the brain: from the neuron alone to its cellular environment and the relationships within it.
Bars also influenced scientific culture, including in the fight against gender discrimination. He died in 2017 at the age of 63. According to the assessment presented in Science, the breadth of his contributions may also have made it difficult to isolate a single discovery worthy of the award: his impact stemmed from an entire research program that changed a field, and not necessarily from a single moment of discovery.
6. The Human Genome Project: An Achievement Greater Than Three Names
The Human Genome Project, which began in 1990, sought to determine the sequence of the approximately three billion base pairs in the human genome. The task required international collaboration, improved sequencing technologies, and the computational capacity to assemble DNA segments into a meaningful sequence.
The difficulty was like putting together a book from a huge number of short, sometimes repetitive, sections. You had to read sections, identify overlaps, and place them correctly. In parallel with the public project, Craig Venter at Celera led a private effort that accelerated the race and also sparked controversy over the commercialization of the information.
In June 2000, the working drafts were announced, and in 2001, the public and private project papers were published. A reference sequence is not a complete decoding of the functioning of the body, nor is it the genome of every person. It provides a framework for comparison: it is possible to identify differences between people, link variants to diseases, and study the activity of genes and other regions of the genome. Even after the publication of the drafts, work continued on completing and improving the sequence.
How do you award a prize to three people for the work of thousands of researchers? The limit on the number of winners, the disputes between the projects, and the debate over access to information are all possible explanations put forward in the Science article. It is impossible to determine which of them actually prevailed. Venter died on April 29, 2026, according to a statement from the institute that bears his name, and can no longer be chosen as a new winner.
The award tells part of the history
The six examples do not prove that every decision by the Nobel Committee was wrong. They show that the history of science is broader than the list of winners. A discovery may become the foundation of an entire field even if its founders did not receive the prize, and certain fields have received recognition for late achievement without their pioneers winning.
Ahead of Monday's announcement, it's also worth remembering the researchers who laid the groundwork: those who identified genetic material, separated memory systems, proved the existence of stem cells, and showed how cells and brains organize. The importance of their work does not depend on the medal.
Questions and Answers
When will the Nobel Prize in Physiology or Medicine be announced in 2026?
On Monday, October 5, at 12:30 PM Israeli time at the earliest. This is the first announcement in the series of awards this year.
Has Science published a prediction for this year's winners?
No. This is a review of six breakthroughs that did not win a Nobel Prize for the achievements described, including researchers who are no longer alive.
Has the stem cell field never won a Nobel?
He was recognized, among other things, in 2012 for reprogramming cells. The loss described here concerns the pioneers who proved the existence and properties of stem cells in the blood system.
Is it known why each of the researchers did not win?
No. It is important to distinguish between facts, such as the limit of three winners and the date of the researcher's death, and assessments regarding skepticism, controversy, or difficulty in distributing credit.
The scientific article
- The original study by Avery, MacLeod, and McCarthy on the transforming agent in bacteria, 1944
- The official Nobel Prize announcement schedule
- Craig Venter Institute announces the passing of its founder on April 29, 2026
