http://www.nytimes.com/2006/07/11/science/11book.html

July 11, 2006

Books

A Peek Into the Remarkable Mind Behind the Genetic Code

By NICHOLAS WADE

Francis Crick is associated with two discoveries, probably two of the 
most important in the 20th century: the double helix of DNA and the 
genetic code. The first he discovered with James Watson; the second 
he worked out mostly by himself, though with contributions from many 
others.

Despite Crick's extraordinary distinction as a scientist, little has 
been written about his life aside from his brief autobiographical 
essay, "What Mad Pursuit," and his leading role in "The Eighth Day of 
Creation," Horace Freeland Judson's outstanding oral history of 
molecular biology.

The first biography of Crick, who died in 2004 at the age of 88, has 
now appeared. Called "Francis Crick, Discoverer of the Genetic Code," 
it is by Matt Ridley, one of the few journalists Crick was in the 
habit of talking with. Mr. Ridley has created a vivid portrait that 
explains Crick's scientific work with clarity, deftly outlines his 
career and provides sharp insights into the nature of Crick's 
remarkable creativity.

Crick, who set a high value on his privacy, seems not to have left 
biographers a great deal to work with beyond what is already on the 
record.

One source of new material developed by Mr. Ridley concerns Crick's 
wartime career in the British Admiralty. Trained as a physicist, 
Crick worked on magnetic and acoustic mines and mine countermeasures. 
Intelligence agents learned that the German minesweepers known as 
Sperrbrechers carried an enormous magnet to make British magnetic 
mines explode harmlessly far ahead of them.

When a Royal Air Force plane photographed a Sperrbrecher with its 
wake cutting through the wash of a mine explosion, Crick realized he 
had the physical information to calculate the weight and strength of 
the magnet. On that basis he designed a mine so insensitive it would 
detonate only right under a Sperrbrecher.

He had considerable trouble persuading British admirals to invest in 
a mine that all other ships passed over unscathed. But that obstacle 
overcome, his devices worked splendidly, sinking more than 100 
Sperrbrechers and stripping German waters of their defenses.

Rejecting a promising career in military physics after the war, Crick 
was influenced by two friends, the Austrian mathematician Georg 
Kreisel and the physicist Maurice Wilkins, to begin a new career in 
biological research.

As Mr. Ridley notes, Crick was in middle age when he embarked on his 
career of scientific discovery, in contrast with the many scientists 
who make their marks when young.

Crick forged his own path through life. Mr. Ridley dwells only 
briefly on Crick's heterodox views and experimental way of life. He 
seldom read newspapers, because working in intelligence had convinced 
him that most stories never reached the press. He experimented with 
marijuana and LSD, Mr. Ridley reports.

Crick and his wife Odile held lively parties and enjoyed the company 
of their many bohemian friends, like John Gayer-Anderson, who made 
pornographic pottery.

"Though they did not have an explicitly 'open marriage,' Francis was 
an incorrigible flirt," Mr. Ridley writes, "and Odile at least 
affected not to mind."

Crick refused to meet the queen when she visited Cambridge's new 
Laboratory of Molecular Biology because he disapproved of royalty, 
and he declined a knighthood. He deeply disliked religion, saying 
once that Christianity was all right between consenting adults but 
should not be taught to children.

He refused to attend weddings or funerals, though he was always up 
for the party afterward. He resigned from Churchill College when it 
decided to build a chapel like any other Cambridge college.

Desire to undercut religious obscurantism was a cogent motive in 
Crick's scientific career, shaping his choice first of the gene and 
later of consciousness as problems that, if cracked, would destroy 
the last refuges of vitalism.

"Throughout, he stayed true to himself: ebullient, loquacious, 
charming, skeptical, tenacious," Mr. Ridley writes in an eloquent 
coda. "He would have liked to find the seat of consciousness and to 
see the retreat of religion. He had to settle for explaining life."

Among the many virtues of this short, beautifully written book are 
the sharp glimpses it offers into a mind of remarkable creativity.

An unusual aspect of Crick's work habits was that his thinking was 
forged in the challenge of argument. This required a constant 
interlocutor or intellectual sparring partner. Mr. Kreisel, the 
mathematician, was the first holder of this unusual position, 
followed by Watson for the discovery of the double helix, Sydney 
Brenner for the work on the genetic code, and Christof Koch for the 
study of the brain and consciousness.

"In the periods when he had no such sounding board he was visibly at 
a loss," Mr. Ridley says.

Another feature of Crick's mind was that he excelled in being able to 
visualize the physical relationship of objects. He could intuitively 
imagine in his mind's eye the space-group symmetry of a crystal's 
unit cell, meaning how far it must be rotated to look the same again. 
A glance at Rosalind Franklin's X-ray photos of DNA told him what she 
had not grasped, that the two parallel chains of the DNA double helix 
must run in opposite directions.

"Although it is necessary to be able to handle the algebraic details, 
I soon found I could see the answer to many of these mathematical 
problems by a combination of imagery and logic, without first having 
to slog through the mathematics," he said.

Another special feature of his approach to science was the difficult 
balance he always maintained between theory and empiricism.

He tried every possible theoretical approach to the problem of how 
the 60 possibilities allowed by a four base triplet genetic code 
might yield 20 kinds of amino acid but never trusted the answers, 
however elegant. That essential caution left him open to the 
empirical approach by which the code was finally broken.

He had the gift of being able to scan vast amounts of confusing 
experimental data, reject parts that seemed not to fit and divine the 
correct answer. Before DNA, biochemists had stamp-collected a large 
number of amino acids. In 1953 Crick and Watson, in sessions at the 
Eagle pub in Cambridge, set out to select some finite number of amino 
acids that DNA might reasonably code for.

Ridley observes: "They came up with 20. That they got the list 
exactly right, despite being amateur biochemists, is a minor miracle."

Crick's special ability to combine his intuitions with theoretical 
and empirical judgment was at its finest in his astonishingly 
prescient paper of 1958 on protein synthesis.

In it he laid out the field's several fundamental axioms, including 
that all proteins are composed of combinations of the same 20 amino 
acids, and that the linear order of amino acids determines the 
three-dimensional structure into which the protein is shaped. "All 
these propositions were guesses," Mr. Ridley writes, "and all are 
correct."

Crick was slow to anger and quick to forgive. He was quite 
unreasonably furious at "The Double Helix," Watson's deep though 
gossipy account of their discovery.

The reason, Mr. Ridley suggests, is that Crick "saw himself as a 
dedicated seeker of great truths who had worked very hard, with long 
hours of reading, calculation, and intuition, to get to the point 
where he could make a great discovery; yet the world would now learn 
about the quest as if it had been just another soap opera."

But the two men were soon friends again, Crick later remarking, "I 
now appreciate how skillful Jim was."

It would be unfair to criticize the author for making essentially the 
same judgments about Crick's historical role as can be found in Mr. 
Judson's book, for both are correct. And it would be quite wrong to 
dismiss Mr. Ridley's biography because it does not contain much new 
information, although in truth it does not.

Mr. Ridley's contribution is that he has extracted from existing 
material a considerably more complete and colorful portrait of Crick 
than has existed before. And by deft narration and analysis, he has 
captured the wonder of an unparalleled scientific mind at work and at 
play.