Rosalind Franklin was the long-overlooked contributor to discovering DNA's structure

X-ray data from Rosalind Franklin was key to discovering DNA’s double-helix structure

Although unpublished, the data reached James Watson and Francis Crick, who worked at another institution. Incorporating her data allowed them to validate their model of DNA, which they published without crediting her.

Rosalind Franklin’s work led to Nobel Prize-winning discoveries in DNA and virology

Her X-ray diffraction imaging helped uncover the structure of DNA, which earned James Watson, Francis Crick, and Maurice Wilkins a Nobel Prize. The same techniques enabled virus imaging, contributing to Aaron Klug's Nobel Prize in chemistry.

The woman erased from the DNA breakthrough

Rosalind Franklin captured “Photo 51,” the key to DNA’s double helix. Her data, shared without her knowledge, helped Watson and Crick win a Nobel. She never got the prize, but today, her role in unlocking life’s blueprint is finally recognized.

Watson's book was described as misleading when detailing Franklin's role in DNA

Despite working together to win the Nobel Prize for their discovery of the structure of DNA, Francis Crick and Maurice Wilkins objected to the publication of James Watson's account of DNA's discovery. Those involved describe how he villainized Rosalind Franklin and downplayed her work.

Beyond DNA, Franklin's legacy extends into modern virology and steel production

While remembered for her critical but under-credited role in uncovering parameters for the structure of DNA, Rosalind Franklin made significant contributions across coal chemistry and virus structure. Her research helped improve fuel efficiency, wartime protective equipment, and foundational knowledge in molecular biology.

Photo 51's distinct 'X' pattern and spacing provided data to validate DNA's model

Rosalind Franklin and Raymond Gosling captured the photo after bombarding DNA fibers with X-rays and observing how the beams were deflected. The photo had a 62-hour exposure time and indicated a helical structure for DNA.

Nature simultaneously published three papers on DNA—only the first made history

Papers by Watson and Crick, Wilkins, and Franklin were fast-tracked without peer review, and their order was arranged between lab heads and editors. Franklin's appeared last, making her paper read as though supporting Watson and Crick—because they'd already incorporated her data before it was published.

Rosalind Franklin uncovered the molecular structure of the tobacco mosaic virus

Franklin's work revealed the role of ribonucleic acid in virus infectivity, contributing to a foundational understanding of genetics and virology. Her molecular model of the virus was featured as the centerpiece at the 1958 Brussels World's Fair.

Watson and Crick revealed DNA's double-helix structure using others' key findings

Their 1953 model, made from cardboard cutouts, explained how DNA stores genetic information through base pairing. Rather than experimenting and collecting their own data, they incorporated patterns and data from other scientists through trial and error.

Explore a 3D model of the experimental setup Rosalind Franklin used to take Photo 51

To capture the X-ray diffraction image of DNA from the thymus of a calf, Franklin built a humidity-controlling camera to isolate the B form of DNA. The exposure lasted 60 hours and produced a cross pattern, indicating a helical structure.

English chemist Rosalind Franklin (1920 - 1958) on the importance of science

"Science and everyday life cannot and should not be separated. Science, for me, gives a partial explanation of life."

The structure of DNA helices comes in three major varieties

The hereditary molecule can take the form of A-DNA, B-DNA, or Z-DNA based on environmental conditions such as ion concentration and humidity—a characteristic identified by Rosalind Franklin. A-DNA is the shortest and widest of the three, while Z-DNA is the longest and narrowest. B-DNA—the most common variety in living cells—is the intermediate.

DNA's four-letter blueprint makes the variety of all living things possible

The proteins responsible for cellular functions and an organism's traits are built outside of a cell's nucleus from RNA—single-stranded molecules created by reading the information in DNA. DNA's double-stranded structure makes it more stable and allows RNA to be made from either of its complementary strands.

Bacteria helped scientists realize that DNA was the hereditary molecule, not proteins

Until the mid-1900s, most scientists believed genes were made of proteins, which were known to act as enzymes, hormones, and other chemicals that mediated an organism's traits. The Avery-MacLeod-McCarty and that benign bacteria could be made lethal, where the inherited factor that caused bacterial transformation contained DNA.

Watch how Sanger sequencing kickstarted the first generation of DNA sequencing

Sanger sequencing is a foundational DNA sequencing technology developed in 1977. The Nobel Prize-winning discovery uses fluorescent dyes at the end of DNA chains, which are sorted by length through electrophoresis, to determine the order of nucleotide bases.

Think we decoded the genome in 2000? Nope. It was 2022.

Two decades after the draft sequence of the human genome was unveiled to great fanfare, a team of 99 scientists has finally deciphered the entire thing. They have filled in vast gaps and corrected a long list of errors in previous versions, giving us a new view of our DNA.

The discovery of nuclear fission was facilitated by the discovery of the neutron

The discovery of the neutron provided scientists with a particle that could penetrate the nucleus and advance atomic physics. Otto Hahn was the sole Nobel recipient for the discovery of fission, despite collaborating with Lise Meitner and Fritz Strassmann.

Drs. Jennifer Doudna and Emmanuelle Charpentier discuss CRISPR

Jennifer Doudna and Emmanuelle Charpentier's were awarded the 2020 Nobel Prize for research focused on understanding and adapting the CRISPR-Cas9 system to precisely edit DNA sequences in other organisms. Doudna has indicated that the system can potentially treat genetic forms of blindness and high cholesterol.

View a collection of historical documents about molecular biology's history

The collection features materials related to those involved in the discovery of DNA and provides historical context for the discoveries of RNA, various viruses, and important bioproteins. The items include photographs, business correspondence, manuscripts, and scientific instruments.

The first criminal conviction through the use of DNA evidence was in 1988

Chromosomes contain markers where short DNA sequences repeat a variable number of times from person to person. A DNA profile is constructed by identifying the number of repeats across 20 regions throughout a genome, which can be compared against a database. DNA paternity tests work similarly by comparing markers between children and their fathers. (Some readers may experience a paywall.)

Watch DNA replicate itself before cell division

In the average adult human, between 50 billion and 70 billion cells die daily, requiring them to replicate their genetic instructions before dividing into new cells. This process relies on various proteins to unwind, read, build, and proofread new strands, with error rates of fewer than one per 1 billion nucleotides.

Visualize how CRISPR-Cas9—a type of immune system used by single-celled organisms to attack invasive viruses—targets and makes precise changes to a gene's DNA.

Despite its potential, CRISPR still fails 15% of the time

Biochemists from UIC found that persistent Cas9 binding to double-strand breaks impacts DNA repair efficiency and the effectiveness of the gene editing tool. RNA polymerase collisions also dislodge Cas9, which affects the efficiency of the tool.

Penicillin was discovered by accident

In 1928, Alexander Fleming returned from vacation to find mold contaminating a petri dish of bacteria. Around the mold, the microbes had died—an accidental observation that led to the discovery of penicillin.

Scientific advances have transformed understanding of Stonehenge’s builders

Techniques such as radiocarbon dating, DNA analysis, and isotopic testing have revised scholars' understanding of Stonehenge. This article presents evidence suggesting that societies were more cooperative and less violent than earlier theories had suggested.

The first line of 'immortal' human cells, which can divide indefinitely and are used in scientific research, was nonconsensually taken from a Black woman.

Examine a 3D model of the Rosetta Stone

One of the most famous archaeological finds of all time, the 1799 discovery of the Rosetta Stone helped unlock the secrets of ancient Egypt. Inscribed on the granite slab was the same passage in three languages: hieroglyphics, Old Egyptian, and Greek, which enabled scholars to decode the ancient language. Take an up-close look with this 3D model made up of more than 200 composite photos.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

The Mona Lisa's celebrity status and repeated restorations have obscured what made the painting so revolutionary for its time

Against his wishes, Albert Einstein's brain was removed before his cremation, and the pathologist responsible stored it for decades in mason jars within a beer cooler.

English mathematician Ada Lovelace wrote the first computer algorithm a century before computers existed and hypothesized that computing devices would one day be able to compose music—foreseeing the generative AI systems of today.

Meet the 56 signers of the Declaration of Independence—most of whom didn't put pen to paper until August 2, 1776—and see their original signatures.

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At the beginning of the 20th century, a group of young men ate standard American food—replete with food additives like borax and formaldehyde—as part of government research to better understand food safety.

Legendary architect Frank Lloyd Wright designed the SC Johnson headquarters in Wisconsin, aiming to make a cathedral-like workplace

A small portion of The Winstons' 'Amen, Brother,' an obscure '60s gospel record, is the basis for thousands of hip-hop tracks, making it one of the most sampled records ever that's informally known as 'the Amen break.'

After her fellow cult members tried to kill her with an LSD-infused hamburger, one member of the Manson Family, the murderous cult led by Charles Manson, decided to testify against the group's leader.

Before humans, the Soviet Union and the United States sent animals—including apes, dogs, and cats—to space during the Space Race.

The name 'Silicon Valley' arose from the founding of Shockley Semiconductor Laboratory in Fairchild Semiconductor in 1956-57, founded near Stanford University in Palo Alto

Ebola is a filovirus, meaning it resembles a thread under a microscope, though it sometimes twists and can resemble a bowl of spaghetti.

Warren Buffett's former professor Benjamin Graham is known as the 'father of value investing,' a strategy in which investors seek to buy stocks trading below their intrinsic worth.

While atoms are normally made of protons, neutrons, and electrons, exotic ones have been built with antimatter—alternate versions of normal matter that live for fractions of a second and are about a billion times as rare.

During the French Revolution, a botanist's letter asking about "dear Rhus" (poison ivy) was intercepted, leading authorities to suspect he was conspiring with the Russians.

Scientists can determine Earth's past climate conditions by analyzing air trapped in microscopic bubbles within ice cores—columns of compressed snow layers that build up over hundreds of thousands of years.

Brandi Chastain, the star of the 1999 US victory over China in the 1999 Women's World Cup, was a last-second choice to take the penalty kick that sealed the victory.

Explore an interactive map built from more than 100,000 survey responses on where people find joy in their lives

Sunflowers have long been a symbol of nuclear disarmament because they can extract large amounts of radioactive cesium from soil.

Some Pokémon have been named after real and fictional organisms, while some real-world species have been named after Pokémon, such as Chilicola charizard and Binburrum zapdos.

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All rainbows are 'raincircles' caused by water droplets separating white sunlight into a spectrum of colors, but Earth's surface blocks the bottom half of the circle from our line of sight.