Hello and welcome to the Witness History Podcast from the BBC World Service.

Today we're going back to 1951 when a young British scientist began one of the most important scientific

investigations of the century. Rosalin Franklin was working at King's College London when she produced an x-ray

photograph that helped work out the 3D structure of DNA, the molecule that

holds the genetic code that underpins all life.

For Hana Haida made this program in 2017.

So what is DNA?

The Molecule of Life is in fact a long chain of 3 billion smaller ones. They're wound up tightly into almost

every cell inside us and they contain the instructions to build and repair the entire human body.

A brilliant but prickly scientist Rosalind Franklin took the crucial photo of the molecule that helped her rivals get their first.

Rosalind Franklin was born in London in 1920 into a modern thinking wealthy Jewish family. I've been speaking to Jennifer

Lynn, Rosalind Franklin's younger sister. It was a very discussing sort of household I think.

Rosalind enjoyed arguments, not aggressively in any way, but she liked discussing things.

So she was someone who spoke her mind, would you say even from a young age.

Certainly.

And my mother wrote a sort of memory of her pointing out that she was

always very logical and very exact and always wanted to know even as a small child would never accept a belief or

statement for which no reason or proof could be produced. I think that's society

I'm a scientist really. With her scientific talent evident at an early age,

Rosalind went to Cambridge in 1938 to study chemistry. After graduation she joined the war effort,

carrying out research to try to make gas masks more effective.

In 1951 she went to work at King's College London,

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