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Elizabeth Blackburn, Ph.D.

Nobel Prize in Medicine

A high school teacher said, 'What's a nice girl like you doing going into science'?

Elizabeth Blackburn was born in Hobart, the capital city of Tasmania, the island that forms the southernmost state in Australia. One of seven children, both of her parents were physicians, and her interest in the science of living things was encouraged from an early age.

When she was in her teens, her family moved to Melbourne, and Blackburn attended Melbourne’s University High School, where a sympathetic teacher further encouraged her interest in science. She earned her bachelor’s and master’s degrees in biology from the University of Melbourne in Australia, and on the advice of her professors, traveled to England to study at Cambridge, where she completed her Ph.D. in 1975. She pursued post-doctoral studies in molecular and cellular biology at Yale University, in the laboratory of Dr. Joseph Gall.

Dr. Elizabeth Blackburn in her lab at Genentech Hall, UCSF. Her 2004 dismissal from the President's Council on Bioethics Research was a cause célèbre in the scientific community. (© Kim Kulish/Corbis)
Dr. Elizabeth Blackburn in her lab at Genentech Hall, University of California in San Francisco. Her 2004 dismissal from the President’s Council on Bioethics Research was a cause célèbre in the scientific community. (Corbis)

Working with the single-celled organism Tetrahymena, one of a class of simple organisms sometimes derisively referred to as “pond scum,” Blackburn uncovered the molecular structure of the telomere, the region at the end of the chromosome that prevents it from disintegrating as the cell reproduces. Telomeres, she found, were repetitive chains of six-nucleotide sequences. Blackburn and her mentor, Joseph Gall, shared these findings in a landmark paper published in 1978.

The same year, Dr. Blackburn joined the faculty of the University of California at Berkeley, where she continued her work on telomeres. Her research suggested the existence of a unique enzyme that regulates the replication of the telomere, continuously rebuilding the ends of chromosomes to protect them in the cells of young organisms, and allowing them to decay in older ones. The identity of this hypothetical enzyme remained elusive. If its existence could be proved, and its mechanism understood, it would be the first step toward a new understanding of the aging process, of degenerative diseases in which healthy young cells suddenly die, and of cancer, where they multiply uncontrollably.

Since this enzyme could not be identified, its action could not be observed, and many experts doubted its existence, proposing alternative explanations for the mysterious life cycle of the telomere. A few years after arriving at Berkeley, Blackburn encountered a recent biology graduate named Carol Greider. Their collaboration would unlock the mystery of the telomere’s regulating enzyme.

Carol Greider, Professor of Molecular Biology and Genetics at Johns Hopkins University School of Medicine. (Courtesy of Dr. Carol Greider)
Carol Greider, Professor of Molecular Biology and Genetics and Bloomberg Distinguished Professor at the Johns Hopkins University School of Medicine.

Carol Greider was born in San Diego, California on April 15, 1961. Both of her parents were scientists: her father a physicist, her mother a biologist. Her mother suffered from depression and committed suicide when Carol was six. She grew up in Davis, California, with her father and an older brother. Although dyslexia made school difficult for her at first, she developed a capacity for memorization that served her well in chemistry and biology classes. By junior high she was showing a distinct aptitude for science.

In her senior year of high school, Greider visited the University of California, Santa Barbara (UCSB), where she was profoundly impressed by a meeting with a biology professor, Dr. Beatrice Sweeney. The following year, she entered UCSB as a biology major. With Dr. Sweeney’s guidance, she soon gravitated toward molecular biology in particular. On graduating in 1983, she considered a number of options for graduate school, but an interview with Elizabeth Blackburn not only convinced her that Berkeley was the school for her, but that she would do her graduate research on telomeres, in Blackburn’s laboratory.

Under Dr. Blackburn’s supervision, Greider threw herself into the search for the telomere’s mysterious regulating enzyme. In what the Lasker Award Committee would later describe as “a tour de force of biochemistry,” Greider tried one method after another to purify and observe the proteins found in the telomeres, trying to discover which, if any, performed the enzymatic activity they were looking for.

A panel discussion with Academy student delegates on the future of medicine at the 2001 Achievement Summit in San Antonio, Texas. Dr. Carol Greider is joined by investor and medical research philanthropist James E. Stowers, the pioneering neurosurgeons Dr. Keith Black and Dr. Benjamin Carson, and neuroscientist Dr. Solomon H. Snyder.

After seven or eight months of dead ends, Greider and Blackburn discussed another possible experiment, using oligonucleotides of DNA produced in a chemical synthesizer, rather than bacteria. Greider’s father was recently divorced and had suffered a heart attack the previous year. Dreading a long holiday at home with an unhappy family, Carol Greider set up the new experiment a few days in advance, and returned to the laboratory on Christmas Day to check the results. She could not have found a more welcome gift. An unfamiliar protein was distinctly visible in the telomere, performing an enzymatic action that looked very much like what Blackburn and others had predicted.

For months afterwards, Blackburn and Greider tested every possible alternative explanation for the activity they were seeing. By spring they were certain. The enzyme they named “telomerase” was regulating the growth of the telomere, adding layers of repetitive DNA to the end of the chromosome when the cell was young, and then turning off, leaving the telomere to wear away and the cell to die.

Dr. Elizabeth Blackburn, at her bench in the Blackburn Laboratory at the University of California, San Francisco in 2008. She had just received the laureate of the L'Oreal-UNESCO Award for Women in Science. (© Micheline Pelletier/Corbis)
Dr. Elizabeth Blackburn, at her bench in the Blackburn Laboratory at the University of California, San Francisco, in 2008. She had just received the laureate of the L’Oreal-UNESCO Award for Women in Science. (Micheline Pelletier)

Their findings created a sensation in the scientific community and soon spread to the popular press. Overenthusiastic journalists saw a cure for cancer — or even a means to reverse the aging process — just around the corner. In fact, Blackburn and Greider had opened the door to a new field of inquiry into these topics, one that may in time lead to new treatments for degenerative diseases, as well as cancer.

Carol Greider remained in Elizabeth Blackburn’s laboratory for four years. After being awarded her Ph.D. in 1987, she was recruited by the Cold Springs Harbor Laboratory, the Long Island research institute led for many years by DNA pioneer James Watson. While continuing her research at Cold Harbor, she lectured at nearby State University of New York, Stony Brook.

Dr. Elizabeth Blackburn in her lab at the University of California, San Francisco, in 2004, shortly after being dismissed from President George W. Bush's Council on Bioethics research. (© Kim Kulish/Corbis)
Dr. Elizabeth Blackburn in her lab at the University of California, San Francisco in 2004. The Australian-American Nobel laureate is currently the President of the Salk Institute for Biological Studies in La Jolla, California. (Corbis)

In 1990, Elizabeth Blackburn moved from Berkeley to the Department of Microbiology and Immunology at the University of California, San Francisco (UCSF). She chaired the department from 1993 to 1997. Carol Greider moved from Cold Springs in 1997 to accept a professorship at Johns Hopkins University School of Medicine in Baltimore, where she is now a professor and Director of the Department of Molecular Biology and Genetics.

From 1996 to 2001, Carol Greider served on the National Bioethics Advisory Commission appointed by President Bill Clinton. Dr. Blackburn was appointed to its successor organization, the President’s Council on Bioethics, in 2001, but soon ran afoul of White House politics. Blackburn supported human embryonic stem cell research, a practice President George W. Bush opposed. In 2004, her service on the council was terminated, prompting outrage from many in the scientific community, who saw an executive branch seeking scientific justification for political decisions, rather than basing science policy on sound research.

Elizabeth Blackburn was the Morris Herzstein Professor of Biology and Physiology at UCSF, serving in both the Department of Microbiology and Immunology, and the Department of Biochemistry and Biophysics. She is currently the President of the Salk Institute for Biological Studies in La Jolla, California. Over the years, they have succeeded in more than doubling the life span of cells in the laboratory. Dr. Greider’s current research focuses on the biochemistry of telomerase, and on the consequences of telomere dysfunction, including the role of telomeres in tumor growth.

Johns Hopkins colleague and past Nobel Prize recipient Peter Agre congratulates Dr. Carol Greider on the 2009 Nobel Prize in Medicine. (Courtesy of Dr. Carol Greider)
Johns Hopkins colleague and past Nobel Prize recipient Dr. Peter Agre congratulates Dr. Carol Greider on the 2009 Nobel Prize in Medicine. Greider pioneered research on the structure of telomeres, the ends of the chromosomes.

As the implications of their discoveries have become more apparent, Blackburn and Greider have been showered with honors, including America’s top medical honor, the Albert Lasker Medical Research Award, in 2006. The following year, Elizabeth Blackburn was named one of Time magazine’s “100 Most Influential People.” Their work received the most public recognition of all in 2009. In awarding Elizabeth Blackburn and Carol Greider the 2009 Nobel Prize in Medicine, the Swedish Academy noted that their discoveries “…have added a new dimension to our understanding of the cell, shed light on disease mechanisms, and stimulated the development of potential new therapies.” Elizabeth Blackburn received the 2012 American Institute of Chemists Gold Medal, as well as, the Royal Medal of the Royal Society for her contributions to the advancement of knowledge. Author Catherine Brady has told Blackburn’s story in the 2007 book  Elizabeth Blackburn and the Story of Telomeres.  Blackburn has shared her findings with the general public in her 2017 book The Telomere Effect: The New Science of Living Younger, which details the relationship of healthy living, telomeres, general health and longevity.

Over the years, Blackburn and Greider have remained close friends, and both have raised families while carrying out their historic research. They continue their research and, as others guided them, they have served as mentors to another generation of research scientists, men and women who will continue their work for years to come.

Inducted Badge
Inducted in 2000

Dr. Elizabeth Blackburn and Dr. Carol Greider are pioneers in the study of telomeres, segments of DNA that help determine the number of times a cell divides, an event that affects the life span and health of cells, and the development of some cancers.

Carol Greider was a graduate student of Dr. Blackburn’s at the University of California, Berkeley, in 1985, when she discovered the enzyme telomerase, which creates telomeres. This discovery has spawned a whole new field of research, with Dr. Blackburn and Dr. Greider in the forefront.

Blackburn and her team at the University of California, San Francisco succeeded in more than doubling the life span of cells in the laboratory, research which may hold promise for controlling age-related and degenerative disorders. Greider’s research at Johns Hopkins University focuses on the biochemistry of telomerase, and on the consequences of telomere dysfunction, including the role of telomeres in cancer.

In awarding Elizabeth Blackburn and Carol Greider the 2009 Nobel Prize in Medicine, the awards committee noted that their discoveries “…have added a new dimension to our understanding of the cell, shed light on disease mechanisms, and stimulated the development of potential new therapies.”

Watch full interview

Dr. Blackburn, could you describe the path that led to the discovery of telomerase? Did you have setbacks along the way, or moments of doubt?

Elizabeth Blackburn: Experiments don’t work much of the time. The very easy ones have been done, so when you do things, you know that there’ll be a certain number of times things just won’t work. You keep trying. You try a different way.

With telomerase, the initial experiments have been done with trying to make certain kinds of fragments of DNA into a kind of a bait, or a lure, to try and lure out telomerase to show us its existence. I’d done a little tiny bit of work with this and seen the tiniest hint, maybe there was something working, and Carol then took this on and said, “Okay, we’re really going to make this work.” But then the breakthrough was to not use fragments of DNA grown in bacteria, but to use very small — what are called oligonucleotides of DNA made in a chemical synthesizer where you can make more, and that is the thing that made a big difference. So you know, it was very hard going, and it wasn’t at all assured of success. So even though it sounds smooth in retrospect, there’s lots of things that didn’t work, and to this day you try things out, and some of them work and some of them don’t. There’s a lot of unpredictability in doing biology experiments, so you have to be able to put up with a lot of times things not appearing to work.

Elizabeth Blackburn and Carol Greider pose with a bust of legendary immunologist Paul Ehrlich, before being awarded the Paul Ehrlich and Ludwig Darmstaedter Science Prize in Frankfurt, Germany in March of 2009. A few months later, they would receive the Nobel Prize as well. (AP Images/Michael Probst)
Elizabeth Blackburn and Carol Greider pose with a bust of legendary immunologist Paul Ehrlich, before being awarded the Paul Ehrlich and Ludwig Darmstaedter Science Prize in Frankfurt, Germany in March of 2009. A few months later, they would both receive the Nobel Prize for Physiology or Medicine as well. (AP/Michael Probst)

Dr. Greider, could you tell us a little bit more about the discovery of the enzyme itself, telomerase. How did you know you had something?

Carol Greider: We started sometime around in May, trying various things to try to devise a way to find something that nobody had ever seen before. So what we had to do was to test out a whole bunch of different things, just empirically, to determine whether or not we could see something. So it was probably seven or eight months of doing that before we made this particular change in the way we did the experiment. So I did the experiment. The experiment was actually set up some time before Christmas time — and these kinds of experiments take four or five days for you to actually get the results. It was on Christmas Day that I came back in and developed the gel and saw this result. That Christmas, and other Christmases, it was important to be in the lab, because family things were very difficult, so I wanted to have something to do. So it was very nice that here I was, trying to keep focused, and something great came out of it.

So I developed the gel that showed this pattern. It looked like the kind of pattern that we might expect, and so I was able to think about it.

One of the things about my interaction with Liz is I always would try and sort of hide away for at least an hour or two with new results. I recall at other times actually turning and going into another room when I saw her coming down the hall, so I could sit and think with my data for about ten minutes because she was always so much quicker than I was at getting to what this essential thing meant. So I did have — because I did develop it on Christmas Day — I had at least a day and a half to sit and think with the results and sort of mull over what they might mean. And then, of course, met with Liz and we went over them together, and because again it was Christmas time, just after that I took off for a trip that I was going to take. So I had another two or three weeks to sit on my own and try and plan out, what did I think the next set of experiments might be, so that I could have some time to sort of think things through, and then was able to come back and we could sit down together with Liz and go over things.

Dr. Carol Greider addresses her colleagues and the press at Johns Hopkins University after learning she has won the Nobel Prize, October 5, 2009. (Courtesy of Dr. Carol Greider)
2009: Greider addresses her colleagues at Johns Hopkins University after learning she has won the Nobel Prize.

It was a lot of fun doing the interactions, the day-to-day interactions, but because she had already thought about things, sometimes much more than I had, I tried to get some independence, so that I could think about them, and then we would put our two heads together, over a matter of days, and come up with new ideas.

Dr. Blackburn, can you remember what you thought when Carol first showed you these results?

Elizabeth Blackburn: Carol had done this experiment, and we stood, just in the lab, and I remember sort of standing there, and she had this — we call it a gel. It’s an autoradiogram, because there was trace amounts of radioactivity that were used to develop an image of the separated DNA products of what turned out to be the telomerase enzyme reaction. I remember looking at it and just thinking, “Ah! This could be very big. This looks just right.” It had a pattern to it. There was a regularity to it. There was something that was not just sort of garbage there, and that was really kind of coming through, even though we look back at it now, we’d say, technically, there was this, that and the other, but it was a pattern shining through, and it just had this sort of sense, “Ah! There’s something real here.” But then of course, the good scientist has to be very skeptical and immediately say, “Okay, we’re going to test this every way around here, and really nail this one way or the other.” If it’s going to be true, you have to make sure that it’s true, because you can get a lot of false leads, especially if you’re wanting something to work.

Was it just the two of you in the lab?

Elizabeth Blackburn: Yes, yes, yes.

Nobel Prize recipient Carol Greider hugs her children, Gwendolyn and Charles, while Johns Hopkins University President Ronald Daniels applauds, following the announcement of Greider's Nobel Prize. (© Matthew Cavanaugh/epa/Corbis)
Dr. Carol Greider hugs her children, Gwendolyn and Charles, while Johns Hopkins University President Ronald Daniels applauds, following the announcement of Greider’s Nobel Prize in Medicine. (Matthew Cavanaugh/Corbis)

Did you share a moment of joy, or were you both immediately skeptical?

Elizabeth Blackburn: I think there was excitement, and then sort of, “Well, what does one do next?”

You don’t dare dwell too long on excitement but — but I did have this, “Ah, yes. This is looking very…” This sort of gut feeling. “This is looking good.” Carol had it. She knew. But again, we had to both do this sort of tough testing of it, and there wasn’t a set of rules by which to test it, so we had to sort of imagine — day, week, month after month — had to imagine all the possible things it could be that would make the whole thing fall on its face and look like it was just a false lead. You had to keep thinking of more and more possibilities, because nature is kind of complicated, and there’s lots of things that can go wrong, and you don’t want to fool yourself. So that process went on for quite a while, but in a way it’s sort of like an intellectual thing. You’re trying to say, “Can you be smarter than nature?” in a way. Can you dig something out that has been hard to find? Telomerase — there’s not a lot of telomerase. This is why it didn’t show up 20 or 30 years ago. There’s not a lot of it. It had to be teased out and distinguished against all of the other kinds of things, all of the other enzymes in cells that do related — but not the same — kinds of things.

How did this discovery of telomerase differ from science that had come before? What was new and significant about it?

Carol Greider: There was a lot of evidence that was already around that there was something going on at the ends of chromosomes, where DNA sequences could be added on to the ends, and that they were dynamic in some manner. There were some competing hypotheses as to how that DNA might be added on to the ends, and there was a very popular competing hypothesis, which was talked about a lot by some famous people who I respected a lot. And that particular thing was a recombination-based model for adding sequences on to the ends of chromosomes. So I do recall feeling a little bit intimidated by the fact that there were some really major groups out there who thought that this same process could be done by a different kind of mechanism. So who was I to think that I could grind up some cells and find some new enzyme that nobody had ever found before? Nevertheless, we thought maybe it’s not done the way they think it’s done. So you come in the lab every day, and do the next experiment, and just keep chugging away like one does a lot of things in life. You just take the next step, and then we found this evidence that the enzyme actually existed.

Carol Greider meets with the media at a news conference in Baltimore, after the announcement of the 2009 Nobel Prize in Medicine. (AP Images/Rob Carr)
Greider meets with the media at a news conference in Baltimore, after the announcement of the 2009 Nobel Prize.

Was there an actual moment when you knew that you were seeing something that hadn’t been described before?

Carol Greider: When I first saw the first result that Christmas Day, there was a pretty clear recognition of what it might be. I remember being very excited, but within hours, all the things went through my mind about what else it could be, but not what I thought. What other things could be fooling me, and look like that, and not really be a new enzyme? So then we set about challenging ourselves to prove that it wasn’t a lot of other things that were already known that were fooling us. I think that the point where I really believed that it really was real — because I wouldn’t even allow myself to believe it — was an experiment. I guess it was the experiment using the yeast oligo, and getting the yeast oligo to do the same thing.

Elizabeth Blackburn in her lab in San Francisco, 2004. (AP Images/Paul Sakuma)
Elizabeth Blackburn in her San Francisco lab, 2004. (AP)

Elizabeth Blackburn: Yes, right.

Carol Greider: It was maybe five or six months later that we actually did that experiment and got the result. I do remember going home that night, having had that result, and just being very excited about it, and thinking, “Okay, this really is something new.” So it was probably a good six months of testing various other alternative hypotheses before really believing it. I remember turning up the rock and roll and dancing all by myself in my room at home.

What song were you dancing to?

Carol Greider: It was Springsteen. Born in the U.S.A. I’m not sure which song, but that’s what the album was.

How about you, Dr. Blackburn? When did you have that feeling you’d got it?

Keys to success — Integrity

Elizabeth Blackburn: Actually, that first gel really sort of — it said so — it was such an unusual pattern to see, that it really spoke and said, “Yes, I think this is it. “And then, of course, as you say, all the questions that any responsible person is going to ask, that this isn’t just wishful thinking. You can always wish to see what you want to see, but there was this real qualitative difference in the previous — you know, there had been a little hint here and this sort of thing — but this was kind of, “Ah!” There was a pattern. You know, I think we love patterns. This produced a kind of pattern of tiger stripes. I think our eyes like to see these sorts of things, and I think our view of how this enzyme works is still very dominated by this kind of visual pattern, but I did have this real gut sense. “Ah yes. This really, really looks important and new here.” So you have these two things that go on inside, so you have this “Yes, this is really good, and I want to do this,” and then at the same time, as Carol was saying this morning, we have to also be very sort of strict, because you know yourself. You’re the most likely to be deluded, because you’re the one who wants it to work, all right. So you also have to kind of play these two things off against each other, where your enthusiasm for the project has to kind of feed into your enthusiasm to make it sure as well, because in science you are trying to get at what is real. Right?