The DNA Revolution
Fifty Years after Watson and Crick, the New Questions in Genetics
Within its double helix structure, DNA -- deoxyribonucleic acid -- carries the genetic instructions for making living organisms.
Image: U.S. Department of Energy Human Genome Program
James Watson, left, and Francis Crick, right, and their model of DNA's structure.
Photo: Courtesy of Science Photo Gallery/Antony Barrington Brown
A Brief History of DNA's Discovery
1865 Gregor Mendel, in experiments with peas, theorizes about how traits are passed on from one generation to the next.
1869 Swiss Scientist Friedrich Miescher isolates a material in cells that will eventually become known as "deoxyribonucleic acid" or DNA. He calls it "nuclein."
1909 German geneticist Wilhelm Johannsen coins the term "gene" to describe units of heredity.
1911 America scientist Thomas Hunt Morgan shows that these units of heredity are located on chromosomes. He receives the Nobel Prize in 1933.
1929 American biochemist Phoebus Levene determines the chemical makeup of DNA, identifying its four bases - - adenine, cytosine, guanine and thymine.
1943 English biochemist William Astbury makes the first X-ray diffraction images of DNA's structure.
1952 Work with viruses and bacteria by American scientists Alfred Hershey and Martha Chase supports the theory that genes are made of DNA.
1953 At Cavendish Laboratory at Cambridge, Francis Crick and James Watson describe the double helix structure of DNA and suggest how genetic material is copied. Their idea of a double helix formation is based on X-ray diffraction images made by Kings College's Rosalind Franklin, who was part of a lab led by Maurice Wilkins. Watson, Crick and Wilkins receive the Nobel Prize in 1962.
For a more in-depth timeline, visit:
Celebrating Life, a joint project by Nature, U.K. Medical Research Council and The Royal Society
The National Human Genome Research Institute
April 2003 -- Fifty years ago this week, a one-page report published in the British science journal Nature revolutionized science. In it, James Watson and Francis Crick described the three-dimensional structure of DNA.
Knowing DNA's structure immediately solved one of biology's greatest mysteries -- how genetic instructions are passed on from one generation to the next. And it opened the door to what has become the hottest area of medical research -- genetics.
Human Genome Project director Francis Collins says, even 50 years later, it's impossible to overstate the importance of knowing the structure of DNA:
"It is so intertwined in every bit of what we do experimentally, in terms of perceiving our own position in the scheme of life on this planet. It has become one of those givens that is so central to your thinking that you stop thinking about it, but if somebody took it away from you, your whole intellectual foundation would collapse, and it would be unimaginable what we would be doing now if we didn't know about the double helix."
To mark the 50th anniversary of Watson and Crick's paper, NPR presents a series of reports on how the discovery has changed research, and what the new biomedical frontiers are.
DNA and Human Identity
The knowledge of how genetic information is carried from one generation to the next raised the specter of a kind of biological determinism, i.e. we are what our genes make us. NPR's Joe Palca examines the extent to which that has turned out to be -- or not to be -- the case. He talks to a pair of identical twins, one of whom is one of the country's leading geneticist, the other a psychologist and counselor. April 22, 2003
DNA and Drug Development
Fifty years on from the discovery of the structure of DNA, the way doctors and drug companies think about developing and prescribing treatments is changing. Hundreds of millions of federal and private dollars are being sunk into research to learn more about how the subtle differences in DNA between one person and another can change a drug's effect, for better or worse. NPR's Joanne Silberner reports. April 23, 2003
DNA and Ethics
NPR's Joe Palca examines how and why scientists temporarily put the brakes on recombinant DNA research -- and how this is relevant to the ongoing debates over human stem cell and cloning research. April 23, 2003
DNA and Dollars
The DNA revolution has led to developments that continue to transform agriculture, food production, medicine and big pharmaceutical companies. Such developments have also transformed the relationship between public and private enterprise, and as NPR's Snigdha Prakash reports, the impact on the U.S. economy has been huge. April 24, 2003
DNA and Human Origins
DNA is not just an instruction book for the present and something to pass on to future generations -- it is also record of our genetic past. No longer do researchers look for clues to human history merely in fossil bones and stone tools, they also seek "genetic fossils" in the DNA of living peoples. NPR's David Baron talks to a University of Maryland researcher, who has revealed some of the most detailed clues yet to humankind's origins. April 24, 2003
DNA and the Brain
As scientists began to understand how genetic material controls the physical machinery of our bodies, most were confident that such research would help unlock the secrets of the brain, including the genetic causes of mental illness. That still hasn't happened. NPR's Jon Hamilton reports on why it's turned out to be so difficult. April 25, 2003
DNA, the Human Computer
For many, the best analogy for the way DNA works is that it's like a computer program at the heart of every cell. Some of its programming tricks bear an uncanny resemblance to ones the human brain has dreamed up on its own. In other ways, DNA works in ways that human programmers find entirely alien. NPR's David Kestenbaum speaks with researchers who are trying to understand this odd and extraordinary piece of software that is the product of billions of years of evolution. April 25, 2003
The Watson and Crick Paper
Read Watson and Crick's classic paper, published in Nature, April 1953. (Requires Adobe Acrobat Reader. Download it for free.)
Get a quick lesson in genetics in this glossary compiled by Genome.gov.
NPR Notable Archive Audio
NPR's Joe Palca reviews Watson and Crick's discovery on its 40th anniversary. February 1993
An international research team announces the completion of the final version of the human genome map, the genetic blueprint of life. NPR's Jon Hamilton reports. Morning Edition, April 15, 2001
Francis Collins, head of the National Institutes of Health's Human Genome Project, talks about what advances genetic research may promise in the next 50 years. Weekend Edition Sunday, April 13, 2003
Science Friday looks back at the discovery of DNA's structure and at what it has meant to science and to the world. Feb. 28, 2003
On Feb. 28, 1953, Francis Crick walked into a pub in Cambridge, England and announced that he and Watson had, "found the secret of life." NPR's Joe Palca reports on the 50th anniversary of that day. Feb. 28, 2003
As researchers announced the completion of the first draft of the human genome, NPR's David Kestenbaum decided to find out what its takes to pull DNA out of a cell and then read it. He accepted an invitation -- not to a lab, but to a kitchen, where a researcher uses a blender to extract DNA from an onion cell. All Things Considered, Feb. 9, 2001