Christie's Biologist Francis Crick drew this sketch of DNA's molecular structure in a seven-page handwritten letter to his son that sold for more than $6 million on Wednesday. "The model looks much nicer than this," Crick wrote.

A 60-year-old letter in which biologist Francis Crick told his son about DNA's double-helix structure, weeks before the Nobel Prize-winning discovery was revealed to the world, sold at a New York auction on Wednesday for a record price of $6 million.

"I'm sort of in a state of shock," said Michael Crick, the son who received that letter in 1953 and held onto it for six decades. "The family is calling me 'The Six Million Dollar Man.'"

The $6,059,750 sale price represents the highest amount ever paid for a letter, said Elizabeth Van Bergen, a spokeswoman for the Christie's auction house. The total price includes the buyer's winning bid of $5.3 million plus the buyer's premium. That sum is roughly three times as much as the pre-sale estimates of the letter's worth ($1 million to $2 million) and more than four times as much as the current Nobel Prize amount ($1.25 million).

The letter was purchased by an anonymous buyer who made the bid over the phone. Half of the proceeds will go to Michael Crick and his wife. The other half will go to the Salk Institute for Biological Studies in California, where the elder Crick worked up until his death in 2004 at the age of 88.

Francis Crick and his American colleague, James Watson, published their DNA findings on April 25, 1953, in the journal Nature. That two-page research paper set the stage for Nobel Prize in 1962 and opened the way for a revolution in genetics that is continuing today.

More than a month before the Nature publication, Crick described DNA's "beautiful" structure in a seven-page, handwritten letter to Michael, who was then a 12-year-old student at a British boarding school. "My dear Michael," the letter began, "Jim Watson and I have probably made a most important discovery."

The father went on to describe the DNA molecule's workings in detail, and drew a diagram of the now-famous twisted-ladder structure.

Bebeto Matthews / AP Michael Crick holds the 1962 Nobel Prize medal that was awarded to his father, with his daughter, Kendra Crick, standing by his side. The medal is to be sold during a New York auction on Thursday.

"As far as we know, it's the first written description of how life comes from life," Michael Crick, now 72, told NBC News. He and other family members decided to sell the letter, as well as Francis Crick's 23-carat gold Nobel Prize medal and other personal effects, during a pair of auctions this week in New York.

The timing was chosen to capitalize on the 60th anniversary of the discovery, and Michael Crick speculated that the timing — and the growing importance of genetics — had something to do with the letter's higher-than-expected price. In addition to the letter, the items sold at Christie's included a sketch of Francis Crick by his wife that went for $17,500; and one of the scientist's notebooks, which sold for $21,250. Those items also brought prices significantly higher than the pre-sale estimates.

Watson, who turned 85 years old this month, was in the audience for Wednesday's sale and shared a bottle of champagne with the Cricks afterward, Michael said.

Francis Crick's Nobel Prize medal and its accompanying diploma are to be sold by Heritage Auctions on Thursday. That lot alone could go for anywhere between $500,000 and several million dollars. Francis Crick's lab coat, his canceled Nobel check and other items will be sold as well. Twenty percent of the proceeds from the Heritage Auctions sale are to be donated to the Francis Crick Institute in London, with the remainder divided among the scientist's heirs.

Michael Crick said he hoped the medal as well as the letter will go on public display to serve as "an inspiration to young scientists all over the world."

The younger Crick has had a long career as a computer programmer and game designer in the Seattle area, and currently puts out a daily series of word puzzles known as "Cricklers." He said he and his wife have already talked about how his new status as a Six Million Dollar Man (or, more accurately, a 2.6 million-dollar man) might change their routine.

"We're very determined not to let it seriously impact our lives," Michael Crick said. "We still want to do our Crickler puzzles every night."

More about the DNA discovery:

For more information about Michael Crick's DNA letter, including a remembrance of his father and a catalog that shows every page of the letter, check out Christie's website. Check the Heritage Auctions website to learn more about the medal and associated sale items.

Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.

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