Rosalind Franklin is best known for her contributions to the study of DNA (deoxyribonucleic acid) and plant viruses. Her experiments with X-ray diffraction—or the use of X rays to create images of crystallized solids—led to her discovery that the sugar-phosphate backbone of DNA lies on the outside of the DNA molecule. Her studies also revealed the helical, or spiral, structure of the molecule. Franklin’s discoveries, which were incorporated into the work of her colleagues, went largely unacknowledged by them, and by scientific history, after her death at the age of 37.

By the 1950s, scientists’ understanding of DNA was nearly complete. DNA is a self-replicating material present in nearly all living organisms, mostly in chromosomes. It functions as a carrier of genetic information that determines hereditary characteristics. Scientists knew that DNA stores all of the information needed to create a living organism; however, they did not yet know what the DNA molecule looked like, or exactly how it performed its role in determining hereditary characteristics. Rosalind Franklin enlightened the world of science through her discoveries.

Born on July 25, 1920, in England to an upper-class Jewish family, Franklin knew that she wanted to be a scientist when she was 15 years old. Her schooling began at St. Paul’s Girls’ School in London. Later, she passed her admissions examination at Cambridge University, much to her father’s dismay. Her family was known for its philanthropic and civic activities, but her father disapproved of higher education for women. Rosalind Franklin’s aunt came to her rescue by insisting that her niece’s intellect was too sharp to neglect. When her mother sided with her aunt, Franklin’s father relented, and Rosalind headed for the hallowed halls of Cambridge, where she took courses in physical chemistry at Newnham College. When she finished her undergraduate degree, she went to work as a physical chemist at the British Coal Utilization Research Association. During World War II (1939–45), Franklin studied a wartime problem: the efficient use of coal, which was a common way to heat homes and businesses when oil was in short supply. Her work in this field helped to launch the field of high-strength carbon fibers. She published five papers on the subject before she reached the age of 26.

In 1947, Franklin began experimenting with X ray diffraction in Paris, working with crystallographer Jacques Mering. In 1951, she accepted an offer to join a team of scientists studying cells at the King’s College Biophysical Laboratory in London. Franklin, trained as a chemist, made an excellent addition to the laboratory. By using the crystallography technique, Franklin was able to locate atoms in a crystal, which could then be mapped by looking at the image of the crystal under an X-ray beam. Crystallography was just coming into use by biologists trying to determine the structure of DNA. Franklin thus brought her expertise with crystallography to the lab at King’s College. Unfortunately, she was treated as a lab assistant rather than as a colleague. As a result, Franklin never received her due recognition.

Rosalind Franklin’s research helped other scientists to build accurate models of the DNA molecule. At the King’s College lab, she built a high-resolution X-ray camera that produced the first usable pictures of DNA ever taken. She found that, depending on the water content, DNA forms two kinds of fibers with different X-ray diffraction patterns. Continuing her analysis, she discovered the sugar-phosphate backbone of DNA on the outside of the molecule and described its helical structure.

Meanwhile, Franklin’s associate at King’s College, Maurice Wilkins (1916– ), showed Franklin’s best X-ray diffraction picture of DNA—which demonstrated the helical structure—to two other scientists at Cambridge University’s Institute of Molecular Biology, James Watson (1928– ), an American, and Francis Crick (1916–2004), a British scientist. Wilkins shared the information without Franklin’s knowledge. Some of Franklin’s findings were also publicized at a seminar, which Watson attended. Watson and Crick went on to build a double helix model of DNA. The scientific journal Nature published three papers on the discovery: one by Rosalind Franklin, one by Watson and Crick, and the third by Wilkins and his colleague, in 1953.

Disliking the atmosphere at King’s College (women scientists, for example, were not allowed to eat in the common room), Franklin began working at the Crystallography Laboratory at Birbeck College in 1953. Continuing the work she had pursued at the British Coal Utilization Research Association, she studied the changes in the shapes of heated carbon. This research became important in atomic technology and in the cooking industry. She then turned her attention to plant viruses, helping to lay the foundation for structural virology. Franklin worked in her lab up until a few weeks before her death from ovarian cancer on April 16, 1958.

In 1962, Wilkins, Watson, and Crick won the Nobel Prize in medicine. The three have been hailed as making the single most important development in biology in the 20th century. Watson described his work on DNA in his 1968 book The Double Helix. In a critique of the book (“Reflections on the Story of the Double Helix,” Women Studies International Quarterly, vol. 2, 1979: 261–273), Ruth Hubbard revealed Watson’s patronizing attitude toward women scientists. For example, Watson described Rosalind Franklin as Wilkins’s assistant at the King’s College laboratory, not as an associate who had been brought in because of her knowledge of X-ray diffraction. Watson goes on to assess Franklin’s attractiveness and grooming habits. He also surmised that Franklin would not last long at King’s College, because she would not allow herself to be dominated by men. In general, Watson paints a picture of science as a field that ought to be pursued by men and not women. In the epilogue to the book, however, Watson recognizes the importance of her work, and also the obstacles women scientists have had to overcome to gain status within the scientific community.