The Discovery of the Molecular Structure of DNA - The Double Helix The Discovery of the Molecular Structure of DNA - The Double Helix A Scientific Breakthrough The sentence "This structure has novel features which are of considerable biological interest" may be one of science's most famous understatements. It appeared in April 1953 in the scientific paper where James Watson and Francis Crick presented the structure of the DNA-helix, the molecule that carries genetic information from one generation to the other. Nine years later, in 1962, they shared the Nobel Prize in Physiology or Medicine with Maurice Wilkins, for solving one of the most important of all biological riddles. Half a century later, important new implications of this contribution to science are still coming to light. What is DNA? The work of many scientists paved the way for the exploration of DNA. Way back in 1868, almost a century before the Nobel Prize was awarded to Watson, Crick and Wilkins, a young Swiss physician named Friedrich Miescher, isolated something no one had ever seen before from the nuclei of cells.

He called the compound "nuclein." This is today called nucleic acid, the "NA" in DNA (deoxyribo-nucleic-acid) and RNA (ribo-nucleic-acid). Francis Crick and James Watson, 1953. Photo: Cold Spring Harbor Laboratory Archives Maurice Wilkins. Two years earlier, the Czech monk Gregor Mendel, had finished a series of experiments with peas. His observations turned out to be closely connected to the finding of nuclein. Mendel was able to show that certain traits in the peas, such as their shape or color, were inherited in different packages. These packages are what we now call genes. For a long time the connection between nucleic acid and genes was not known. But in 1944 the American scientist Oswald Avery managed to transfer the ability to cause disease from one strain of bacteria to another. But not only that: the previously harmless bacteria could also pass the trait along to the next generation. What Avery had moved was nucleic acid. This proved that genes were made up of nucleic acid.

Solving the Puzzle In the late 1940's, the members of the scientific community were aware that DNA was most likely the molecule of life, even though many were skeptical since it was so "simple." They also knew that DNA included different amounts of the four bases adenine, thymine, guanine and cytosine (usually abbreviated A, T, G and C), but nobody had the slightest idea of what the molecule might look like. In order to solve the elusive structure of DNA, a couple of distinct pieces of information needed to be put together. One was that the phosphate backbone was on the outside with bases on the inside; another that the molecule was a double helix. It was also important to figure out that the two strands run in opposite directions and that the molecule had a specific base pairing. As in the solving of other complex problems, the work of many people was needed to establish the full picture. The original DNA model by Watson and Crick. Photo: Cold Spring Harbor Laboratory Archives Using X-rays to See Through DNA Watson and Crick used stick-and-ball models to test their ideas on the possible structure of DNA. Other scientists used experimental methods instead.

Among them were Rosalind Franklin and Maurice Wilkins, who were using X-ray diffraction to understand the physical structure of the DNA molecule. When you shine X-rays on any kind of crystal – and some biological molecules, such as DNA, can form crystals if treated in certain ways – the invisible rays bounce off the sample. The rays then create complex patterns on photographic film. By looking at the patterns, it is possible to figure out important clues about the structures that make up the crystal. "Photograph 51". X-ray diffraction photo of a DNA molecule, structure B. Photo: Cold Spring Harbor Laboratory Archives A Three-Helical Structure? The scientist Linus Pauling was eager to solve the mystery of the shape of DNA. In 1954 he became a Nobel Laureate in Chemistry for his ground-breaking work on chemical bonds and the structure of molecules and crystals. In early 1953 he had published a paper where he proposed a triple-helical structure for DNA. Watson and Crick had also previously worked out a three-helical model, in 1951. But their theory was wrong.

Their mistake was partly based on Watson having misremembered a talk by Rosalind Franklin where she reported that she had established the water content of DNA by using X-ray crystallographic methods. But Watson did not take notes, and remembered the numbers incorrectly. Instead, it was Franklin's famous "photograph 51" that finally revealed the helical structure of DNA to Watson and Crick in 1953. This picture of DNA that had been crystallized under moist conditions shows a fuzzy X in the middle of the molecule, a pattern indicating a helical structure. Model of the alpha helix, 1951. Photo: Oregon State University's Special Collections Specific Base-Pairing The base-pairing mystery had been partly solved by the biochemist Erwin Chargoff some years earlier. In 1949 he showed that even though different organisms have different amounts of DNA, the amount of adenine always equals the amount of thymine. The same goes for the pair guanine and cytosine. For example, human DNA contains about 30 percent each of adenine and thymine, and 20 percent each of guanine and cytosine.

With this information at hand Watson was able to figure out the pairing rules. On the 21st of February 1953 he had the key insight, when he saw that the adenine-thymine bond was exactly as long as the cytosine-guanine bond. If the bases were paired in this way, each rung of the twisted ladder in the helix would be of equal length, and the sugar-phosphate backbone would be smooth. Structure Shows Action "It has not escaped our notice that the specific pairing we have postulated immediately suggests a possible copying mechanism for the genetic material" wrote Watson and Crick in the scientific paper that was published in Nature, April 25, 1953. This was indeed a breakthrough in the study of how genetic material passes from generation to generation. Once the model was established, its mere structure hinted that DNA was indeed the carrier of the genetic code and thus the key molecule of heredity, developmental biology and evolution. The specific base pairing underlies the perfect copying of the molecule, which is essential for heredity. During cell division, the DNA molecule is able to "unzip" into two pieces.

One new molecule is formed from each half-ladder, and due to the specific pairing this gives rise to two identical daughter copies from each parent molecule. We All Share the Same Building Blocks DNA is a winning formula for packaging genetic material. Therefore almost all organisms – bacteria, plants, yeast and animals – carry genetic information encapsulated as DNA. One exception is some viruses that use RNA instead. Different species need different amounts of DNA. Therefore the copying of the DNA that precedes cell division differs between organisms. For example, the DNA in E. coli bacteria is made up of 4 million base pairs and the whole genome is thus one millimeter long. The single-cell bacterium can copy its genome and divide into two cells once every 20 minutes. The DNA of humans, on the other hand, is composed of approximately 3 billion base pairs, making up a total of almost a meter-long stretch of DNA in every cell in our bodies. In order to fit, the DNA must be packaged in a very compact form. In E. coli the single circular DNA molecule is curled up in a condensed fashion, whereas the human DNA is packaged in 23 distinct chromosome pairs. Here the genetic material is tightly rolled up on structures called histones.

A New Biological Era This knowledge of how genetic material is stored and copied has given rise to a new way of looking at and manipulating biological processes, called molecular biology. With the help of so-called restriction enzymes, molecules that cut the DNA at particular stretches, pieces of DNA can be cut out or inserted at different places. In basic science, where you want to understand the role of all the different genes in humans and animals, new techniques have been developed. For one thing, it is now possible to make mice that are genetically modified and lack particular genes. By studying these animals scientists try to figure out what that gene may be used for in normal mice. This is called the knockout technique, since stretches of DNA have been taken away, or knocked out. Scientists have also been able to insert new bits of DNA into cells that lack particular pieces of genes or whole genes. With this new DNA, the cell becomes capable of producing gene products it could not make before. The hope is that, in the future, diseases that arise due to the lack of a particular protein could be treated by this kind of gene therapy.

Photo: Cold Spring Harbor Laboratory Archives Many voices have argued that the Nobel Prize should also have been awarded to Rosalind Franklin, since her experimental data provided a very important piece of evidence leading to the solving of the DNA structure. In a recent interview in the magazine Scientific American, Watson himself suggested that it might have been a good idea to give Wilkins and Franklin the Nobel Prize in Chemistry, and him and Crick the Nobel Prize in Physiology or Medicine – in that way all four would have been honored. Rosalind Franklin died in 1958. As a rule only living persons can be nominated for the Nobel Prize, so the 1962 Nobel Prize was out of the question. The Nobel archives, at the Nobel Prize-awarding institutions, that among other things contain the nominations connected to the prizes, are held closed. But 50 years after a particular prize had been awarded, the archives concerning the nominees are released. Therefore, in 2008 it was possible to see whether Rosalind Franklin ever was a nominee for the Nobel Prize concerning the DNA helix. The answer is that no one ever nominated her - neither for the Nobel Prize in Physiology or Medicine nor in Chemistry.

The DNA-Helix The sugar-phosphate backbone is on the outside and the four different bases are on the inside of the DNA molecule. The two strands of the double helix are anti-parallel, which means that they run in opposite directions. The sugar-phosphate backbone is on the outside of the helix, and the bases are on the inside. The backbone can be thought of as the sides of a ladder, whereas the bases in the middle form the rungs of the ladder. Each rung is composed of two base pairs. Either an adenine-thymine pair that form a two-hydrogen bond together, or a cytosine-guanine pair that form a three-hydrogen bond. The base pairing is thus restricted. This restriction is essential when the DNA is being copied: the DNA-helix is first "unzipped" in two long stretches of sugar-phosphate backbone with a line of free bases sticking up from it, like the teeth of a comb. Each half will then be the template for a new, complementary strand. Biological machines inside the cell put the corresponding free bases onto the split molecule and also "proof-read" the result to find and correct any mistakes.

After the doubling, this gives rise to two exact copies of the original DNA molecule. The coding regions in the DNA strand, the genes, make up only a fraction of the total amount of DNA. The stretches that flank the coding regions are called introns, and consist of non-coding DNA. Introns were looked upon as junk in the early days. Today, biologists and geneticists believe that this non-coding DNA may be essential in order to expose the coding regions and to regulate how the genes are expressed. By Lotta Fredholm, Science Journalist First published 30 September 2003 READ MORE Who Discovered DNA? - Nobel Prize Winners Wilkins, Crick and Watson Who Discovered DNA? Share this page on your website: <a href="">Who Discovered DNA?</a> Who discovered DNA? This is the story of the Nobel Prize Winners Wilkins, Crick and Watson and DNA discovery/development. This article is a part of the guide: Select from one of the other courses available: Discover 11 more articles on this topic Don't miss these related articles: .

DNA - The Molecule of Life Deoxyribonucleic acid or DNA is the hereditary material present in the cells of all humans and other living organisms. DNA is a nucleic acid generally regarded as a blueprint, a recipe or a code of an organism. The blueprint contains instructions which enable development of cells in to body. And also controls the characteristics featured in a fully functional living structure through genes. The very first cell in a living being is formed when egg and sperm get mingled. At that point DNA molecule renders the entire genetic code to be used for the formulation of cells forever in that creature. These cells divide and replicate themselves perfectly to construct the body structure. They continue to do that for body maintenance as well i.e. formation of new blood cells or skin cells. The Nucleotides are the basic structural unit of DNA. Each Nucleotide is a pair of polymers with backbones made up of sugar and phosphate groups connected by ester bonds. The two anti-parallel strands run freely in the nucleus. Four types of bases are attached to each sugar. The arrangement of these bases along the backbone encrypts information which is accessed through transcription using the genetic code. In each cells, DNA molecules are systematically arranged into longitudinal structures called chromosomes.

During the process of DNA replication, chromosomes duplicate themselves before cells divide. . Discovery of DNA - Three Main Players "This structure has novel features which are of considerable biological interest." This statement, perhaps the most scientific understatement, appeared in April 1953 in the scientific journal "Nature" when Watson and Crick presented the structure of the DNA-helix. In 1962, they shared Nobel Prize in Physiology or Medicine with Maurice Wilkins. Their brief life stories follow. Francis Crick (1916-2004) As a boy, Francis Crick had a keen interest in physics, chemistry, and mathematics. Before World War II, he studied physics at University College in London. For two years after the war he was admitted to the British Admiralty Research Laboratory. He was influenced by the works of Erwin Schrödinger to alter his professional career from physics to biology. After working at a Cambridge University laboratory he joined Cavendish Laboratory at Cambridge in 1949. The scope of his learning included biology, organic chemistry, protein structure and x-ray diffraction technology. In 1951, he was joined by James Watson.

Both of them worked closely and presented their visual model of DNA in 1953. They shared Nobel Prize in 1962. He continued his professional career in various institutions and authored couple of books in later years. James Watson (b. 1928) The American born James Watson was obsessed with bird-watching in his childhood. In 1947, at the age of 15 he graduated from the University of Chicago. He received his Ph.D. in Zoology from Indiana University in 1950. Then he joined Cavendish laboratories where he worked together with Francis Crick to ascertain DNA structure. In 1953, when they created the model of DNA double helix, it was regarded as an enormous achievement in fields of molecular genetics and biochemistry. For their work Crick, Watson, and Wilkins were awarded the Nobel Prize in 1962. Before becoming director of Cold Spring Harbor Laboratory New York in 1968, Watson taught at Harvard and CalTech. In 1988, as an acknowledgement of his scientific glory and his administrative capabilities, he was appointed appointment as the head of the Human Genome Project at the NIH.

Maurice Wilkins (1916-2004) Maurice Wilkins was a New Zealand born British biophysicist and molecular biologist. After his early education he studied physics in Cambridge at St. John's College and acquired his degree in 1938. Then, in 1940 he received, from University of Birmingham, his Ph.D. in physics. For two years he worked at the Manhattan Project at the University of California, Berkeley during World War II. After that he returned to King's College London. In 1945 he joined St. Andrews' University, Scotland as lecturer in physics and pursued research in biophysics. He worked with Raymond Gosling and Rosalind Franklin during 1950-52. Their combined efforts produced the images of the DNA molecule which resulted in Crick & Watson model in 1953. Wilkins became Deputy Director of the Medical Research Council Unit in 1955 and taught biophysics at King's College. In addition to the Nobel Prize in 1962, he was also given the Albert Lasker Award by American Public Health Association in 1960.

He shared both the awards with Watson and Crick. Later, in 1962 he was made a Commander of the British Empire. . DNA Research: A Timeline of Discovery & Developments 1866 BBC - History - Crick and Watson z James Watson and Francis Crick, 1959 © Crick and Watson, together with Maurice Wilkins, won the 1962 Nobel Prize in Medicine for their discovery of the structure of DNA. This was one of the most significant scientific discoveries of the 20th century. Francis Harry Compton Crick was born on 8 June 1916 near Northampton. He studied physics at University College, London, and during World War Two worked for the Admiralty on the development of mines. He changed from physics to biology and in 1947 began to work at Cambridge University. By 1949 he was working at the Medical Research Council unit at the Cavendish Laboratory in Cambridge. In 1951 an American student, James Watson, arrived at the unit and the two began to work together.

James Dewey Watson was born on 6 April 1928 in Chicago and studied at the universities of Chicago, Indiana and Copenhagen. He then moved to Cambridge University. Watson and Crick worked together on studying the structure of DNA (deoxyribonucleic acid), the molecule that contains the hereditary information for cells. At that time Maurice Wilkins and Rosalind Franklin, both working at King's College, London, were using X-ray diffraction to study DNA. Crick and Watson used their findings in their own research. In April 1953, they published the news of their discovery, a molecular structure of DNA based on all its known features - the double helix. Their model served to explain how DNA replicates and how hereditary information is coded on it. This set the stage for the rapid advances in molecular biology that continue to this day. Watson, Crick and Wilkins shared the Nobel Prize in Medicine in 1962. Franklin had died in 1958 and, despite her key experimental work, the prize could not be received posthumously. Crick and Watson both received numerous other awards and prizes for their work.

Francis Crick continued to work in genetics and then moved into brain research, becoming a professor at the Salk Institute for Biological Studies in California. He died on 28 July 2004. From 1988 to 1992, James Watson directed the Human Genome Project at the American National Institutes of Health. He was instrumental in obtaining funding for the project and in encouraging cooperation between governments and leading scientists. A Science Odyssey: People and Discoveries: Watson and Crick describe structure of DNA Watson and Crick describe structure of DNA 1953 Photo: Model of DNA molecule In the late nineteenth century, a German biochemist found the nucleic acids, long-chain polymers of nucleotides, were made up of sugar, phosphoric acid, and several nitrogen-containing bases. Later it was found that the sugar in nucleic acid can be ribose or deoxyribose, giving two forms: RNA and DNA. In 1943, American Oswald Avery proved that DNA carries genetic information. He even suggested DNA might actually be the gene.

Most people at the time thought the gene would be protein, not nucleic acid, but by the late 1940s, DNA was largely accepted as the genetic molecule. Scientists still needed to figure out this molecule's structure to be sure, and to understand how it worked. In 1948, Linus Pauling discovered that many proteins take the shape of an alpha helix, spiraled like a spring coil. In 1950, biochemist Erwin Chargaff found that the arrangement of nitrogen bases in DNA varied widely, but the amount of certain bases always occurred in a one-to-one ratio. These discoveries were an important foundation for the later description of DNA. In the early 1950s, the race to discover DNA was on. At Cambridge University, graduate student Francis Crick and research fellow James Watson (b. 1928) had become interested, impressed especially by Pauling's work. Meanwhile at King's College in London, Maurice Wilkins (b. 1916) and Rosalind Franklin were also studying DNA. The Cambridge team's approach was to make physical models to narrow down the possibilities and eventually create an accurate picture of the molecule.

The King's team took an experimental approach, looking particularly at x-ray diffraction images of DNA. In 1951, Watson attended a lecture by Franklin on her work to date. She had found that DNA can exist in two forms, depending on the relative humidity in the surrounding air. This had helped her deduce that the phosphate part of the molecule was on the outside. Watson returned to Cambridge with a rather muddy recollection of the facts Franklin had presented, though clearly critical of her lecture style and personal appearance. Based on this information, Watson and Crick made a failed model. It caused the head of their unit to tell them to stop DNA research. But the subject just kept coming up. Franklin, working mostly alone, found that her x-ray diffractions showed that the "wet" form of DNA (in the higher humidity) had all the characteristics of a helix. She suspected that all DNA was helical but did not want to announce this finding until she had sufficient evidence on the other form as well. Wilkins was frustrated. In January, 1953, he showed Franklin's results to Watson, apparently without her knowledge or consent.

Crick later admitted, "I'm afraid we always used to adopt -- let's say, a patronizing attitude towards her." Watson and Crick took a crucial conceptual step, suggesting the molecule was made of two chains of nucleotides, each in a helix as Franklin had found, but one going up and the other going down. Crick had just learned of Chargaff's findings about base pairs in the summer of 1952. He added that to the model, so that matching base pairs interlocked in the middle of the double helix to keep the distance between the chains constant. Watson and Crick showed that each strand of the DNA molecule was a template for the other. During cell division the two strands separate and on each strand a new "other half" is built, just like the one before. This way DNA can reproduce itself without changing its structure -- except for occasional errors, or mutations. The structure so perfectly fit the experimental data that it was almost immediately accepted. DNA's discovery has been called the most important biological work of the last 100 years, and the field it opened may be the scientific frontier for the next 100.

By 1962, when Watson, Crick, and Wilkins won the Nobel Prize for physiology/medicine, Franklin had died. The Nobel Prize only goes to living recipients, and can only be shared among three winners. Were she alive, would she have been included in the prize? Related Features James Watson, Francis Crick, Maurice Wilkins, and Rosalind Franklin | Chemical Heritage Foundation Search James Watson, Francis Crick, Maurice Wilkins, and Rosalind Franklin These four scientists—Watson, Crick, Franklin, and Wilkins—codiscovered the double-helix structure of DNA, which formed the basis for modern biotechnology. Home / Learn / Historical Biographies At King’s College London, Rosalind Franklin obtained images of DNA using X-ray crystallography, an idea first broached by Maurice Wilkins. Franklin’s images allowed James Watson and Francis Crick to create their famous two-strand, or double-helix, model. In 1962 Watson (b.

1928), Crick (1916–2004), and Wilkins (1916–2004) jointly received the Nobel Prize in Physiology or Medicine for their 1953 determination of the structure of deoxyribonucleic acid (DNA). Wilkins’s colleague Franklin (1920–1958), who died from cancer at the age of 37, was not so honored because the Nobel Prize can be awarded only to the living. Discovering the Structure of DNA The molecule that is the basis for heredity, DNA, contains the patterns for constructing proteins in the body, including the various enzymes. A new understanding of heredity and hereditary disease was possible once it was determined that DNA consists of two chains twisted around each other, or double helixes, of alternating phosphate and sugar groups, and that the two chains are held together by hydrogen bonds between pairs of organic bases—adenine (A) with thymine (T), and guanine (G) with cytosine (C).

Modern biotechnology also has its basis in the structural knowledge of DNA—in this case the scientist’s ability to modify the DNA of host cells that will then produce a desired product, for example, insulin. The background for the work of the four scientists was formed by several scientific breakthroughs: the progress made by X-ray crystallographers in studying organic macromolecules; the growing evidence supplied by geneticists that it was DNA, not protein, in chromosomes that was responsible for heredity; Erwin Chargaff’s experimental finding that there are equal numbers of A and T bases and of G and C bases in DNA; and Linus Pauling ’s discovery that the molecules of some proteins have helical shapes—arrived at through the use of atomic models and a keen knowledge of the possible disposition of various atoms. Courtesy Vittorio Luzzati. Rosalind Franklin Of the four DNA researchers, only Rosalind Franklin had any degrees in chemistry. She was born into a prominent London banking family, where all the children—girls and boys—were encouraged to develop their individual aptitudes. She attended Newnham College, one of the women’s colleges at Cambridge University.

She completed her degree in 1941 in the middle of World War II and undertook graduate work at Cambridge with Ronald Norrish, a future Nobel laureate. She resigned her research scholarship in just one year to contribute to the war effort at the British Coal Utilization Research Association. There she performed fundamental investigations on the properties of coal and graphite. She returned briefly to Cambridge, where she presented a dissertation based on this work and was granted a PhD in physical chemistry. After the war, through a French friend, she gained an appointment at the Laboratoire Centrale des Services Chimiques de l’Etat in Paris, where she was introduced to the technique of X-ray crystallography (see video on this page) and rapidly became a respected authority in this field. In 1951 she returned to England to King’s College London, where her charge was to upgrade the X-ray crystallographic laboratory there for work with DNA. Video of Viewing History through the Corrective Lenses of the Spectrophotometry and X-Ray Crystallography History through Spectrophotometry and X-Ray Crystallography explains how these instruments help understand structure of atoms.

Maurice Wilkins Maurice Wilkins with X-ray crystallographic equipment about 1954. Courtesy King’s College London and Horace Freeland Judson. Already at work at King’s College was Maurice Wilkins, a New Zealand–born but Cambridge-educated physicist. As a new PhD he worked during World War II on the improvement of cathode-ray tube screens for use in radar and then was shipped out to the United States to work on the Manhattan Project. Like many other nuclear physicists, he became disillusioned with his subject when it was applied to the creation of the atomic bomb; he turned instead to biophysics, working with his Cambridge mentor, John T. Randall—who had undergone a similar conversion—first at the University of St. Andrews in Scotland and then at King’s College London. It was Wilkins’s idea to study DNA by X-ray crystallographic techniques, which he had already begun to implement when Franklin was appointed by Randall. The relationship between Wilkins and Franklin was unfortunately a poor one and probably slowed their progress. James Watson and Francis Crick Meanwhile, in 1951, 23-year-old James Watson, a Chicago-born American, arrived at the Cavendish Laboratory in Cambridge.

Watson had two degrees in zoology: a bachelor’s degree from the University of Chicago and a doctorate from Indiana University, where he became interested in genetics. He had worked under Salvador E. Luria at Indiana on bacteriophages, the viruses that invade bacteria in order to reproduce—a topic for which Luria received a Nobel Prize in Physiology or Medicine in 1969. Watson went to Denmark for postdoctoral work, to continue studying viruses and to remedy his relative ignorance of chemistry. At a conference in the spring of 1951 at the Zoological Station at Naples, Watson heard Wilkins talk on the molecular structure of DNA and saw his recent X-ray crystallographic photographs of DNA. He was hooked. James Watson and Francis Crick with their DNA model at the Cavendish Laboratories in 1953. To request permission to use this photo, please visit the Science Photo Library website at . © A. Barrington Brown. Watson soon moved to the Cavendish Laboratory, where several important X-ray crystallographic projects were in progress.

Under the leadership of William Lawrence Bragg, Max Perutz was investigating hemoglobin and John Kendrew was studying myoglobin, a protein in muscle tissue that stores oxygen. (Perutz and Kendrew received the Nobel Prize in Chemistry for their work in the same year that the prize was awarded to the DNA researchers—1962.) Working under Perutz was Francis Crick, who had earned a bachelor’s degree in physics from University College London and had helped develop radar and magnetic mines during World War II. Crick, another physicist in biology, was supposed to be writing a dissertation on the X-ray crystallography of hemoglobin when Watson arrived, eager to recruit a colleague for work on DNA. Inspired by Pauling’s success in working with molecular models, Watson and Crick rapidly put together several models of DNA and attempted to incorporate all the evidence they could gather. Franklin’s excellent X-ray photographs, to which they had gained access without her permission, were critical to the correct solution. The four scientists announced the structure of DNA in articles that appeared together in the same issue of Nature. Separate Career Paths Then they moved off in different directions. Franklin went to Birkbeck College, London, to work in J. D.

Bernal’s laboratory, a much more congenial setting for her than King’s College. Before her untimely death from cancer she made important contributions to the X-ray crystallographic analysis of the structure of the tobacco mosaic virus, a landmark in the field. By the end of her life she had become friends with Francis Crick and his wife and had moved her laboratory to Cambridge, where she undertook dangerous work on the poliovirus. Wilkins applied X-ray techniques to the structural determination of nerve cell membranes and of ribonucleic acid (RNA)—a molecule that is associated with chemical synthesis in the living cell—while rising in rank and responsibility at King’s College. Watson’s subsequent career eventually took him to the Cold Spring Harbor Laboratory (CSHL) of Quantitative Biology on Long Island, New York, where as director from 1968 onward he led it to new heights as a center of research in molecular biology. From 1988 to 1992 he headed the National Center for Human Genome Research at the National Institutes of Health. Afterward he returned to CSHL, from which he retired in 2007.

During Crick’s long tenure at Cambridge, he made fundamental contributions to unlocking the genetic code. He and Sydney Brenner demonstrated that each group of three adjacent bases on a single DNA strand codes for one specific amino acid. He also correctly hypothesized the existence of “transfer” RNA, which mediates between “messenger” RNA and amino acids. After 20 years at Cambridge, with several visiting professorships in the United States, Crick joined the Salk Institute for Biological Studies in La Jolla, California. Further Recognition In 2005 James Watson was honored with the Othmer Gold Medal from CHF, for his scientific talent, which has given the world a new intellectual understanding of the nature of life, making possible modern biotechnology and a better life for all mankind. Visit the Museum at CHF to learn more about these four scientists. The information contained in this biography was last updated on July 22, 2015. CHF Awards The Nobel Prize in Physiology or Medicine 1962 - Perspectives Perspectives The Nobel Prize in Physiology or Medicine 1962 Francis Crick, James Watson, Maurice Wilkins Share this: What is Life?

Erwin Schrödinger's idea that physics could help solve biological riddles was the spark that led many researchers to try to unlock the secrets behind our book of life, the structure of DNA. The double helix structure of DNA is arguably the most recognizable icon in biology, so it might at first appear strange that two of the three men awarded the Nobel Prize for its discovery were physicists. However, as all three Laureates, Maurice Wilkins , James Watson and Francis Crick acknowledged, their interest in DNA was sparked not by a biologist, but by a series of lectures delivered by a physicist. These lectures were published in a book in 1944 that sold more than 100,000 copies, ranking it among the most influential scientific writings of the 20th century. Less than 100 pages long, What is Life? is based on the lectures that Erwin Schrödinger gave at Trinity College in Dublin in February 1943. Schrödinger, an Austrian physicist, had become famous in the 1920s for his work on quantum theory.

Key amongst his achievements was his wave equation, for which he was awarded the Nobel Prize in Physics in 1933. Schrödinger had given up his position as a professor at the University in Berlin in 1933 in protest against Nazi persecutions of his Jewish colleagues. In 1940, after seven restless years of exile, Schrödinger accepted an invitation by the Irish premier Eamon de Valera, a mathematician by training, to join the newly founded Dublin Institute for Advanced Studies. Schrödinger conceived the series of lectures he gave at the Institute to be "one small comment on a large and important question". The question Schrödinger addressed was: "How can the events in space and time which take place within the spatial boundary of a living organism be accounted for by physics and chemistry?" The Book of Life Schrödinger's attempts to answer this question would influence a generation of physicists to apply their knowledge to solving biological problems. Schrödinger offered valuable insights into how physics could help solve issues like the basis of heredity.

As Schrödinger wrote in his book, two great theories of physics and biology were born in 1900: Max Planck discovered quantum theory, and de Vries, Correns and Tschermak re-discovered Mendel's forgotten paper on genetics. Yet, while quantum theory had fundamentally changed the perception of the world within three decades, geneticists were still more or less clueless about heredity, wrote Schrödinger. Despite some progress in chromosome research, genes were still very much an abstract concept, and many biologists were still convinced by the idea of an immaterial 'vital force'. One exception to this theory was a paper published by the German physicist Max Delbrück and the Russian geneticist Timofèeff-Ressovsky in 1935. They proposed that genes were large molecules, consisting of bonds of thousand of atoms. This exciting new perspective on genes provided the basis for Schrödinger's lectures. "If the Delbrück picture should fail, we would have to give up further attempts," said Schrödinger. Looking at heredity from his perspective, Schrödinger argued that life could be thought of in terms of storing and passing on biological information.

Understanding life, which would invariably involve discovering the gene, could possibly go beyond the laws of physics as was known at the time, he stated. Building on this belief, Schrödinger proposed a mind-expanding metaphor in his last lecture. Because so much information had to be packed into every cell, it must be packed into what Schrödinger called a 'hereditary code-script' embedded in the molecular fabric of chromosomes. To understand life, then, we would have to identify these molecules, and crack their code. Schrödinger's metaphor of a readable book of life, a decipherable genetic code, might seem obvious now, but at the time this was a sensationally new concept. Schrödinger viewed the genes in each cell as resembling offices that produce orderly events. "Since we know the power this tiny central office has in the isolated cell, do they not resemble stations of local government dispersed through the body, communicating with each other with great ease, thanks to the code that is common to all of them?" asked Schrödinger.

Even Schrödinger appreciated the scale of his suggestion, admitting "Well, this is a fantastic description, perhaps less becoming a scientist than a poet." Such a mind-expanding metaphor resonated loudly with scientists. "The notion that life might be perpetuated by means of an instruction book inscribed in a secret code appealed to me," Watson would later say. The question was what sort of code could hold all the secrets of a living cell, and how could it make exact copies of itself every time a chromosome duplicates? Uncanny Timing However, the main reason behind the successful impact of What is Life? was due to a happy coincidence. In May 1943, Oswald Avery at the Rockefeller Institute in New York published the results of a study that at long last had discovered the source of heredity. To many people's surprise, Avery's experiments proved that it wasn't proteins, as had been widely thought, but in fact a nucleic acid living in chromosomes that was long presumed to be inert, called DNA, short for deoxyribonucleic acid. So, just as Schrödinger's suggestions about a readable book of life were being published, Avery had discovered the very code-script that scientists could now attempt to decipher.

Schrödinger's concept of a highly complex molecular structure that controlled living processes was instrumental in changing Wilkins' career. Wilkins had been involved in the Manhattan Project that created the atomic bomb during the Second World War. He became disillusioned with physics after seeing the fruits of these labours, and was looking for a new research field to explore. One idea in particular struck a chord with Wilkins. Schrödinger proposed that a gene could be stable from one generation to another if it is an 'aperiodic' crystal – in other words, something with a regular but non-repeating structure. Schrödinger compared the difference in the structure of a normal and aperiodic crystal with the difference between ordinary wallpaper in which the same pattern is repeated again and again in a masterpiece of embroidery, such as a Raphael tapestry. Schrödinger's concept of defining genes in terms of crystals interested Wilkins as he had studied the way electrons move in perfect and irregular crystals for his PhD. In 1946, the physicist John Randall recruited Wilkins to a new biophysics laboratory in King's College, London, that he was heading up.

Randall wanted to hire physicists to work on problems in biology, and Wilkins jumped at the chance to work on proteins and DNA. Crick thought the arguments that Schrödinger set out were not without its flaws, but he was still impressed by the book. Crick, also a physicist, had worked on magnetic mines for the Admiralty during the war, and had planned to stay on in military research. After reading What is Life?, he thought a physicist could do more about solving the secrets of life, and joined the Cavendish Laboratory in Cambridge to pursue the three-dimensional structure of proteins for his PhD. To a student called James Watson in his final year at the University of Chicago, the book was an almost instant epiphany. Watson had planned to be a naturalist, but after reading the book he was convinced from Avery's experiments that genes were molecules, and that he should discover the structure of the gene. Watson travelled to Indiana University and the University of Copenhagen in pursuit of his obsession. During his time in Copenhagen, he attended a small conference on X-ray diffraction methods for determining the three-dimensional structure of molecules.

To his delight, he chanced upon a talk by Wilkins, who was presenting data on X-ray diffraction studies of DNA. The array of spots on the photograph indicated that DNA must have a regular structure, and solving this could help reveal the nature of the gene. An excited Watson tried to talk to Wilkins afterwards, but the conversation went no further than a self-evident declaration from Wilkins that much hard work lay ahead. Meeting of Minds Watson's PhD supervisor arranged for him to take up a position at the Cavendish Laboratory, and he arrived in Cambridge in September 1951. Three weeks later Watson discovered that he was sharing space in the biochemistry room with Crick. Watson describes their first meeting as an instantaneous meeting of minds. Crick was interested in the fact that Watson's mission was to discover the structure of DNA, and within minutes they were guessing what the structure could look like. But how could they begin to find out the truth? To bring them up to speed on the latest findings on DNA's structure, Crick invited an old friend to his house for Sunday lunch. The friend, Wilkins, accepted the invitation, and the rest, as they say is history.

Watson and Crick's paper on the double helix structure of DNA was published in the journal Nature on 25 April 1953, and a grateful Crick wrote to Schrödinger on 12 August 1953 to express his gratitude for being an influence. "Watson and I were once discussing how we came to enter the field of molecular biology, and we discovered that we had both been influenced by your little book What is Life?" wrote Crick. "We thought you might be interested in the enclosed reprints – you will see that it looks as though your term 'aperiodic crystal' is going to be a very apt one." Bibliography Blumenberg, Hans: Der genetische Code und seine Leser. In: Die Lesbarkeit der Welt. Suhrkamp, Frankfurt 1999, S. 372–409. Gribbin, John: The scientists. A history of science told through the lives of its greatest inventors. Random House, New York, 2004. Schrödinger, Erwin: What is Life? The physical aspect of the living cell.

With Mind and Matter and Autobiographical Sketches, Cambridge University Press, 1992. Watson, James D.: The Double Helix. A personal account of the discovery of the structure of DNA. Penguin Books, Harmondsworth, 1969. Watson, James D.: DNA: The Secret of Life. Arrow Books, 2004. Wilkins, Maurice H.F., The molecular configuration of nucleic acids, Nobel lecture, December 11, 1962. Wilkins, Maurice: The Third Man of the Double Helix. An Autobiography. Oxford, 2003. By Joachim Pietzsch , for Nobelprize.org James Watson Biography: Co-Discoverer of DNA's Double Helix James Watson Biography: Co-Discoverer of DNA's Double Helix By Mary Bagley, LiveScience Contributor | October 11, 2013 06:25pm ET MORE James Watson, one of the discoverers of the double helix.

Credit: National Library of Medicine James Watson was a pioneer molecular biologist who is credited, along with Francis Crick and Maurice Wilkins, with discovering the double helix structure of the DNA molecule. The trio won the Nobel Prize in Medicine in 1962 for their work. Early life James Dewey Watson was born in Chicago, Ill., on April 6, 1928. He attended Horace Mann Grammar School and then South Shore High School. At the age of 15, he transferred to the University of Chicago in an experimental scholarship program for gifted youngsters. A lifelong interest in birds led him to study biology, and he was awarded his Bachelor of Science degree in zoology in 1947. He switched to genetics shortly after reading Erwin Schrodinger’s seminal book, "What is Life?" After being turned down by the California Institute of Technology and Harvard, Watson won a scholarship to the University of Indiana for post-graduate study. In 1950, he was awarded his doctoral degree in zoology for his work on the effects of X-ray radiation on replication of bacteriophage viruses.

From Indiana, Watson moved to Copenhagen, where he continued his virus research as a Merck Fellow of the National Research Council. After attending a meeting at the Cold Spring Harbor Laboratory in New York, where he heard the results of the Hershey/Chase research, Watson became convinced that DNA was the molecule responsible for transmitting genetic information. He became fascinated with the thought that, if the structure of the DNA molecule were understood, it would be possible to deduce how genetic information is passed between cells. His virus research did not interest him as much as this new line of inquiry. In the spring of 1951, he met Maurice Wilkins at a conference in Naples. Wilkins was showing the results of the first attempts to use X-ray diffraction to photograph DNA molecules. Watson, excited by Wilkins’ results, moved to England in the fall. He went to work at Cavendish Laboratory where he began working with Francis Crick . Early attempts Watson and Crick decided to use a model-building approach to try to discern the molecular structure of the DNA molecule. Both were convinced that understanding the molecular geometry would be central to discovering how DNA could transmit genetic information from parent to daughter cells.

The men understood that discovering the structure of the DNA molecule would be a major scientific breakthrough, and they knew they were in competition with other scientists, such as Linus Pauling, who were also working on DNA. Watson and Crick had difficulty with their first attempts to build a DNA model. Neither man had a degree in chemistry, so they used standard chemistry texts to cut out cardboard models of chemical bonding configurations. A visiting graduate student pointed out that new information, not yet corrected in the text books, showed that Watson was using one of his cardboard chemical bonds backwards. About this time, Watson attended a lecture given by Rosalind Franklin at nearby Kings College. He apparently did not pay close attention. In an essay in 1992, Watson wrote: “I won’t say, but I heard it wrong. … I had heard her talk wrong and I thought there was very little water in it (DNA) and therefore it should be a very compact structure … We said ‘Well, there are four types of bases. There is no way we can stick in a regular sequence of bases in the center in a regular fashion.’” As a result of Watson’s mistake, the men’s first attempt at building a DNA model was a notable failure.

Watson and Crick built a three-stranded helix with the nitrogen bases on the outside of the structure. When they unveiled the model to colleagues, Franklin was scathing in her criticism. Her research results had plainly shown there were two forms of DNA, the wetter B form was clearly what Watson and Crick were trying to model, but they were trying to build the structure without the moisture she had shown was present. She pointed out that, when her research was applied correctly, the nitrogen bases belonged on the inside of the molecular structure. Embarrassed by this public failure, the director of the Cavendish lab told Watson and Crick to abandon their model-building efforts. Both men officially turned to other research but privately continued to think about the DNA problem. Wilkins, who worked at Kings College with Franklin, was having some personality conflicts with her. Franklin was so unhappy at Kings that she had determined to move her research elsewhere. It is unclear how Wilkins came to be in possession of one of her best X-ray images of the DNA molecule; she may even have given it to him as she was clearing her office.

It is clear though that he removed the image from the lab without Franklin’s permission and showed it to his friend, Watson, at Cavendish. In "The Double Helix," Watson wrote: "The instant I saw the picture my mouth fell open and my pulse began to race. The pattern was unbelievably simpler than those obtained previously ('A Form'). Moreover, the black cross of reflections which dominated the picture could only arise from a helical structure." Useful information Watson and Crick used the new information to construct a new double-stranded helix model with the nitrogen bases paired A to T and C to G in the center. This base pairing immediately suggested to Crick that one side of the molecule could serve as a template to exactly replicate DNA sequences to pass on genetic information during cell reproduction. This second, successful model was unveiled in February 1951. In April 1953, they published their findings in the journal Nature, leading to presentation of the Nobel Prize in 1962. The Nobel Prize was shared among Watson, Crick and Wilkins. Nobel Prize rules state that it must be awarded to no more than three living scientists. Franklin had died of ovarian cancer in 1958.

Wilkins did mention her in passing. Watson went on to work with many others throughout the 1950s. His genius appears to be his ability to coordinate the work of different individuals and combine their results into new conclusions. In 1952, he used a rotating anode X-ray to demonstrate the helical construction of the tobacco mosaic virus. From 1953 to 1955, he worked with scientists at the California Institute of Technology to build a plausible model of RNA structure. From 1955 to 1956, he again worked with Crick on discovering principals of virus construction. In 1956, he moved to Harvard where he worked on RNA and protein synthesis. In 1968, Watson published "The Double Helix," a somewhat sensationalized account of the DNA discovery. In the book, Watson used derogatory comments and rancorous personal descriptions of many people involved in the discovery, especially Franklin. Because of this, Harvard Press refused to print the book. However, it was commercially published and was a great success.

In a later edition, Watson excused his treatment of Franklin by stating that he had been unaware of the pressures she faced as a woman doing scientific research in the 1950s. Watson’s greatest financial support came from publishing two textbooks – "Molecular Biology of the Gene" (1965) and "Molecular Biology of the Cell and Recombinant DNA" (updated 2002), which are still in print. In 2007, he published an autobiography, "Avoid Boring People, Lessons from a Life in Science." Later work & controversies In 1968, Watson became the director of the Cold Spring Harbor Laboratory. At the time, the institution was struggling financially, but Watson proved to be very good at raising funds for research. Under Watson’s leadership, Cold Spring became one of the world’s leading institutions for research in molecular biology. In 1990, Watson was named head of the Human Genome Project by the National Institute of Health. He used his fund-raising acumen to pilot the project through until 1992. He resigned over a conflict about patenting genetic information.

Watson believed any commercial patents would only hinder the pure research being done by scientists working on the project. His tenure at Cold Harbor ended abruptly. On Oct. 14, 2007, on his way to a conference in London he was questioned about world events. He responded by saying he was “inherently gloomy about the prospect of Africa … all our social policies are based on the fact their intelligence is the same as ours — whereas the testing says not really.” He continued with the idea that Africa’s progress had been hindered by inferior genetic material. Public outcry over these remarks prompted Cold Spring to ask for his resignation. Watson later apologized and retracted his statements saying, “There is no scientific basis for such a belief.” In his resignation speech, Watson expressed his vision that “the final victory (over cancer and mental illness) is within our grasp." Despite this public setback, Watson continues to enjoy making controversial statements even today. At a meeting hosted in Seattle by the Allen Institute for Brain Science in September 2013, Watson again made controversy when he announced his belief that the increase in diagnosed hereditary disorders might be due to parents having children later in life.

“The older you are, the greater chance you will be carrying these (defective genes),” Watson said, also expressing his idea that genetic material should be collected from people no more than 15 years old for the later production of children via in-vitro fertilization. He believes this will reduce the chances that parents will have their lives “messed up” by the birth of a child with physical or mental disorders. Latest on James Watson Biography: Co-Discoverer of DNA's Double Helix James Watson to sell Nobel prize medal he won for double helix discovery - Telegraph Science News James Watson to sell Nobel prize medal he won for double helix discovery Sale could fetch $3.5 million, money which DNA pioneer says he will use to ensure the academic world remains a place for great ideas James Dewey Watson, the American molecular biologist, best known as one of the co-discoverers of the structure of DNA. Photo: ADAM NADEL By Rob Crilly , New York 12:54AM GMT 27 Nov 2014 Follow Prof James Watson is selling the Nobel Prize medal he won for his role in the discovery of the structure of DNA.

Christie's auction house says it is the first to be sold by a living Nobel laureate and the gold medal could fetch as much as $3.5 million (£2.2 million) at its sale on December 4. Prof Watson made the discovery in 1953 at Cambridge University with Francis Crick. They were jointly awarded the 1962 Nobel Prize in Medicine with Maurice Wilkins, from King's College London, for identifying the elegant double helix in work that laid the basis for modern molecular biology. "All we could say when we got it: It's so beautiful!" he said of the discovery in an interview with CNN last year. Later he became a well-known populariser of science, giving talks and writing books designed to reach a new audience. Related Articles 'DNA could have been found earlier' 13 Jun 2013 His best-selling memoir from 1968, The Double Helix, is credited with changing the public perception of scientists, from staid figures ensconced in laboratories to quick-thinking, ambitious and oftentimes competitive individuals in a race to discover the mysteries of life. Prof Watson said part of the proceeds would go to the institutions where he studied and worked.

"I look forward to making further philanthropic gifts to Cold Spring Harbor Laboratory, the University of Chicago, and Clare College Cambridge, so I can continue to do my part in keeping the academic world an environment where great ideas and decency prevail," he said. The auction also includes many of his papers. Handwritten notes for his acceptance speech are estimated at $300,000 to $400,000. James Watson selling Nobel prize 'because no-one wants to admit I exist' - Telegraph Science James Watson selling Nobel prize 'because no-one wants to admit I exist' World-famous biologist James Watson said he is selling the Nobel Prize medal he won in 1962 for discovering the structure of DNA because he has been ostracised and needs the money James Watson, co-discoverer of the structure of DNA Photo: Alamy By Keith Perry 6:15PM GMT 28 Nov 2014 James Watson, the world-famous biologist who was shunned by the scientific community after linking intelligence to race, said he is selling his Nobel Prize because he is short of money after being made a pariah.

Mr Watson said he is auctioning the Nobel Prize medal he won in 1962 for discovering the structure of DNA, because "no-one really wants to admit I exist". Auctioneer Christie’s said the gold medal, the first Nobel Prize to be sold by a living recipient, could fetch as much as $3.5m (£2.23m) when it is auctioned in New York on Thursday. The reserve price is $2.5m. Mr Watson told the Financial Times he had become an “unperson” after he “was outed as believing in IQ” in 2007 and said he would like to use money from the sale to buy a David Hockney painting. Mr Watson, who shared the 1962 Nobel Prize for uncovering the double helix structure of DNA, sparked an outcry in 2007 when he suggested that people of African descent were inherently less intelligent than white people.

Related Articles Letter from scientist who discovered DNA sells for $5.3m 11 Apr 2013 If the medal is sold Mr Watson said he would use some of the proceeds to make donations to the “institutions that have looked after me”, such as University of Chicago, where he was awarded his undergraduate degree, and Clare College, Cambridge. Mr Watson said his income had plummeted following his controversial remarks in 2007, which forced him to retire from the Cold Spring Harbor Laboratory on Long Island, New York. He still holds the position of chancellor emeritus there. “Because I was an ‘unperson’ I was fired from the boards of companies, so I have no income, apart from my academic income,” he said. He would also use some of the proceeds to buy an artwork, he said. “I really would love to own a [painting by David] Hockney”. Francis Wahlgren, the Christie’s auctioneer who is handling the sale of the medal, said he was confident it would fetch the $2.5m (£1,598347) reserve.

He said demand for memorabilia associated with genetic discovery had “exploded” in recent years as the promise of biotechnology became apparent. “The far-reaching aspects of their discovery affect everybody and are only being appreciated now,” said Mr Wahlgreen. The auctioneer said he did not expect the controversy surrounding Mr Watson’s comments to deter potential buyers. “I think the guy is the greatest living scientist. There are a lot of personalities in history we’d find fault with – but their discoveries transcend human foibles,” he said Auctions for memorabilia and art have been setting new records recently as investors look for inflation-proof investments. Earlier this month Christie’s brought in the highest-ever total for an auction at its contemporary sale in New York. The sale grossed $852.9m across 75 lots, including $25.9m for Jeff Koons’s Balloon Monkey sculpture. Mr Watson – who insisted he was “not a racist in a conventional way” – said it had been “stupid” of him to not realise that his comments on the intelligence of African people would end up in an article. “I apologise . . .

[the journalist] somehow wrote that I worried about the people in Africa because of their low IQ – and you’re not supposed to say that.” In 2007, the Sunday Times ran an interview with Dr Watson in which he said he was “inherently gloomy about the prospect of Africa” because “all our social policies are based on the fact that their intelligence is the same as ours – whereas all the testing says not really”. He told the newspaper people wanted to believe that everyone was born with equal intelligence but that those “who have to deal with black employees find this not true”. Mr Watson said he hoped the publicity surrounding the sale of the medal would provide an opportunity for him to “re-enter public life”. Since the furore in 2007 he has not delivered any public lectures. “I’ve had a unique life that’s allowed me to do things. I was set back. It was stupid on my part. All you can do is nothing, except hope that people actually know what you are,” he said. Prof Watson made his scientific discovery in 1953 at Cambridge University with Francis Crick.

They were jointly awarded the 1962 Nobel Prize in Medicine with Maurice Wilkins, from King's College London, for identifying the elegant double helix in work that laid the basis for modern molecular biology. Mr Watson said he one day wanted his children to auction the handwritten manuscript for his famous book, The Double Helix. “It will be worth a lot more. We’d have a reserve of at least $10m,” he said. Watson and Crick discover chemical structure of DNA - Feb 28, 1953 - HISTORY.com This Day In History: 02/28/1953 - DNA Structure Discovered On February 28th many historical events occurred. These events are recapped by Russell Mitchell in this video clip from "This Day in History". The discovery of DNA by James Watson and Frances Crick being a major one for the scientific community. Not only was DNA discovered on this day, but the Republican Party was founded in Wisconsin. The well-known album Thriller by Michael Jackson won eight Emmy awards as well.

Lead Story Watson and Crick discover chemical structure of DNA Share this: Watson and Crick discover chemical structure of DNA Author Watson and Crick discover chemical structure of DNA URL Publisher A+E Networks On this day in 1953, Cambridge University scientists James D. Watson and Frances H.C. Crick announce that they have determined the double-helix structure of DNA, the molecule containing human genes. Though DNA–short for deoxyribonucleic acid–was discovered in 1869, its crucial role in determining genetic inheritance wasn’t demonstrated until 1943. In the early 1950s, Watson and Crick were only two of many scientists working on figuring out the structure of DNA. California chemist Linus Pauling suggested an incorrect model at the beginning of 1953, prompting Watson and Crick to try and beat Pauling at his own game. On the morning of February 28, they determined that the structure of DNA was a double-helix polymer, or a spiral of two DNA strands, each containing a long chain of monomer nucleotides, wound around each other.

According to their findings, DNA replicated itself by separating into individual strands, each of which became the template for a new double helix. In his best-selling book, The Double Helix (1968), Watson later claimed that Crick announced the discovery by walking into the nearby Eagle Pub and blurting out that “we had found the secret of life.” The truth wasn’t that far off, as Watson and Crick had solved a fundamental mystery of science–how it was possible for genetic instructions to be held inside organisms and passed from generation to generation. Watson and Crick’s solution was formally announced on April 25, 1953, following its publication in that month’s issue of Nature magazine. The article revolutionized the study of biology and medicine. Among the developments that followed directly from it were pre-natal screening for disease genes; genetically engineered foods; the ability to identify human remains; the rational design of treatments for diseases such as AIDS; and the accurate testing of physical evidence in order to convict or exonerate criminals. Crick and Watson later had a falling-out over Watson’s book, which Crick felt misrepresented their collaboration and betrayed their friendship.

A larger controversy arose over the use Watson and Crick made of research done by another DNA researcher, Rosalind Franklin, whose colleague Maurice Wilkins showed her X-ray photographic work to Watson just before he and Crick made their famous discovery. When Crick and Watson won the Nobel Prize in 1962, they shared it with Wilkins. Franklin, who died in 1958 of ovarian cancer and was thus ineligible for the award, never learned of the role her photos played in the historic scientific breakthrough. Related Videos

Question: What did Watson, Crick and Wilson discover in 1953, and for which they were awarded the Nobel Prize for Medicine in 1962?
Answer: (Structure of) DNA