Document Deep Dive: Francis Crick Explains the ‘Secret of Life’

In a heartfelt letter to his son, the scientist who helped discover DNA explains his earth-shattering findings

On March 19, 1953, an eager Francis Crick, still reeling with excitement from his lab work, sat down to write his son a letter. He cut right to the chase. “Jim Watson and I have probably made a most important discovery,” he told Michael, then 12 years old and studying at Bedales, a boarding school in southern England.

Crick and James Watson, a fellow biologist at Cavendish Laboratory at University of Cambridge, had discovered the double-helix structure of DNA. In the endearing seven-page note, written clearly but with high expectations of his young son, Crick describes DNA as being “like a code” and explained how its bases—guanine, adenine, thymine and cytosine—pair up to hold together two twisting strands of molecules. He also spells out how DNA replicates itself. “Read this carefully so that you understand it. When you come home we will show you the model,” Crick instructs, before signing off, “Lots of love, Daddy.”

Until this past spring, the 60-year-old letter was sitting in Michael’s safety deposit box, in an envelope with leaves of acid-free paper placed between each page. “It seemed a bit of a waste,” says Michael Crick, now 72 and living in Bellevue, Washington.

As an adult, Michael can read the letter and appreciate how similarly he and his late father’s minds work. While Michael did not pursue a career in genetics, he has been successful in another manner of coding. He helped design Arpanet, the prequel to the Internet, and the first spell-check tool for Microsoft Word. But, he also realizes the document’s significance to science.

“It is the first written description of what my father calls ‘how life comes from life,’” he says.

In April, Michael and his family sold the letter at Christie’s. The auction house valued the letter at $1 to $2 million, but, ultimately, an anonymous collector shelled out $5.3 million—the highest amount for a letter in auction history. (The buy ousted an Abraham Lincoln letter from this top rank.) The earnings were split between the Crick family and the Salk Institute, Francis Crick’s former employer and a stakeholder in the letter.

Click on the yellow tabs, within the document, to learn more about the letter.

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