FrancisCrickLetter_e_0410A bidder paid over $6 million at an auction today (April 10) for a letter British scientist Francis Crick wrote to his 12-year-old son explaining the double-helix structure of the DNA molecule, which he and James Watson had just discovered.

The winning bid was $5.3 million, with the final price tag for the “Secret of Life” letter coming in at $6,059,750, according to Christie’s, which handled the sale.

The seven-page handwritten note, dated March 19, 1953, contains diagrams that outline the scientists’ model for how “des-oxy-ribose-nucleic-acid” replicates and encodes instructions for the development and function of living things. [See Images of the Francis Crick Letter]

The auction was handled by Christie’s, which had valued the letter at $1-2 million dollars, comparing it to a letter Albert Einstein wrote to President Franklin D. Roosevelt warning about the potential of nuclear weapons. Christie’s sold that letter in 2002 for just over $2 million.

According to Christie’s, Crick’s family plans to give half of the proceeds from the sale of the DNA letter to the Salk Institute in California, where the scientist, who died in 2004, studied consciousness later in his career.

One of Crick’s notebooks, (valued between $4,000 and $6,000) snagged a $17,000 bid. And a drawing of Crick made by his wife, Odile Crick, an artist who drew the double helix for her husband and Watson, was auctioned off for $14,000 today. (Christie’s had estimated it would sell for $8,000-$12,000).

Those three items were among the Crick-related mementos on sale this week in New York. Tomorrow (April 11), Heritage Auctions will sell the Nobel medal, struck in 23-carat gold, that Crick received for the discovery in 1962, alongside Watson and Maurice Wilkins.