Rosalind Franklin: DNA's unsung hero - Cláudio L. Guerra

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The discovery of the structure of DNA was one of the most important scientific achievements in human history. The now-famous double helix is almost synonymous with Watson and Crick, two of the scientists who won the Nobel prize for figuring it out. But there’s another name you may not know: Rosalind Franklin. Cláudio L. Guerra shares the true story of the woman behind the helix.

Lesson by Cláudio L. Guerra , animation by Chris Bishop.

The discovery of the structure of DNA

was one of the most important scientific
achievements in the last century,

in human history, in fact.

The now-famous double helix is almost
synonymous with Watson and Crick,

two of the scientists who won
the Nobel Prize for figuring it out.

But there's another name
you may know, too,

Rosalind Franklin.

You may have heard that her data supported
Watson and Crick's brilliant idea,

or that she was a plain-dressing,
belligerent scientist,

which is how Watson actually described her
in "The Double Helix."

But thanks to Franklin's biographers,

who investigated her life
and interviewed many people close to her,

we now know that that account
is far from true,

and her scientific contributions
have been vastly underplayed.

Let's hear the real story.

Rosalind Elsie Franklin was born
in London in 1920.

She wanted to be a scientist ever
since she was a teenager,

which wasn't a common or easy
career path for girls at that time.

But she excelled at science anyway.

She won a scholarship to Cambridge
to study chemistry,

where she earned her Ph.D.,

and she later conducted research on
the structure of coal

that led to better gas masks for
the British during World War II.

In 1951, she joined King's College

to use x-ray techniques to study
the structure of DNA,

then one of the hottest topics in science.

Franklin upgraded the x-ray lab
and got to work

shining high-energy x-rays
on tiny, wet crystals of DNA.

But the acadmemic culture at the time
wasn't very friendly to women,

and Franklin was isolated
from her colleagues.

She clashed with Maurice Wilkins,

a labmate who assumed Franklin
had been hired as his assistant.

But Franklin kept working,

and in 1952, she obtained Photo 51,
the most famous x-ray image of DNA.

Just getting the image took 100 hours,

the calculations necessary to analyze it
would take a year.

Meanwhile, the American biologist
James Watson

and the British physicist Francis Crick

were also working
on finding DNA's structure.

Without Franklin's knowledge,

Wilkins took Photo 51
and showed it to Watson and Crick.

Instead of calculating the exact
position of every atom,

they did a quick analysis
of Franklin's data

and used that to build
a few potential structures.

Eventually, they arrived at the right one.

DNA is made of two helicoidal strands,

one opposite the other with bases
in the center like rungs of a ladder.

Watson and Crick published their model
in April 1953.

Meanwhile,
Franklin had finished her calculations,

come to the same conclusion,

and submitted her own manuscript.

The journal published
the manuscripts together,

but put Franklin's last,

making it look like her experiments just
confirmed Watson and Crick's breakthrough

instead of inspiring it.

But Franklin had already
stopped working on DNA

and died of cancer in 1958,

never knowing that Watson and Crick
had seen her photographs.

Watson, Crick, and Wilkins won
the Nobel Prize in 1962

for their work on DNA.

It's often said that Franklin would have
been recognized by a Nobel Prize

if only they could be
awarded posthumously.

And, in fact, it's possible
she could have won twice.

Her work on the structure of viruses
led to a Nobel for a colleague in 1982.

It's time to tell the story of a brave
woman who fought sexism in science,

and whose work revolutionized
medicine, biology, and agriculture.

It's time to honor
Rosalind Elsie Franklin,

the unsung mother of the double helix.