Sir

Floods of ink, electronic and actual, have been spent on celebrating the fiftieth anniversary of the discovery of DNA's structure, recollecting facts and testimonies from the protagonists (see http://www.nature.com/nature/dna50/index.html). A gripping correspondence that I recently uncovered among the papers acquired by Jeremy Norman in Novato, California, adds a further motif of reflection on one much-debated episode.

The facts are well known. André Lwoff of the Pasteur Institute in Paris, reviewing Jim Watson's book The Double Helix (Athenaeum, New York; 1968), highlighted a crucial sentence that implied a breach of faith by Max Perutz, who seemed to have given key scientific material to his colleagues Watson and Crick (Scientific American 219, 133–137; 1968), without permission. Soon after, biochemist Erwin Chargaff denounced Perutz for the same reason (Science 159, 1448–1449; 1968).

The precious information was part of a Medical Research Council (MRC) report that Sir John Randall, director of King's College London, had circulated to all the members of the Biophysics Research Committee, including Perutz, who visited his unit on 15 December 1952. As Watson and Crick both acknowledged, the report, containing Rosalind Franklin's precise measurements, gave them an important clue that helped them unravel the antiparallel nature of DNA and scoop both the London team and Linus Pauling of Caltech.

A year later, Perutz published a rebuttal to Lwoff and Chargaff, in which he described the non-confidential nature of the MRC report (Scientific American 221, 8; 1969 and Science 164, 1537–1538; 1969). Why did it take him so long to respond?

What was not known until now is that Perutz's brief rebuttals were the result of backstage scientific teamwork starting in 1968. This correspondence, which I have now uncovered, offers a fascinating look at a chorus of scientists determined to set an official version of events before the public, and gives an insider perspective on the politics of scientific discovery.

“As you may have gathered,” Perutz wrote to a colleague, “I am anxious to correct a story in Watson's book which suggests that I gave Watson and Crick a confidential report... I have now drawn up the enclosed letter which I propose to send to the Scientific American and to Science ... Randall, Wilkins, Gosling and Crick have all agreed. So have Lwoff ... and Chargaff. ... Watson is writing an addition to my letter, with an apology for having misrepresented the incident.”

Perutz, who died early last year (see Nature 415, 851–852; 2002), was an extraordinary experimentalist, a hard worker at the bench and a cautious man of science. Not interested in the rat race, he just wanted to solve problems. This time, the issue was to prove his innocence. “Watson asked ... why I had not shown the report to [Watson] and Crick immediately,” he wrote to Randall. “Was it because I did not want them to get on with the model, etc? And if the report was not confidential, then surely there was no need to ask your permission to show it to them.”

Perutz went into the historical evidence, scrupulously interviewing his colleagues and MRC administrators while going through his initial draft, sentence by sentence, to build up a definitive version.

Two letters in particular are worth mentioning. Randall's prompt reaction to being asked whether it was wise to open the lid was to firmly advise leaving it to the historians. Maurice Wilkins, however, took the opposite view, because he thought that science and its discoveries belong to scientists, in the sense that they are the only ones who can fully understand them and therefore say what the true facts are.

To quote the biochemist John Edsall, presenting Perutz's letter to the editor of Science: “An important issue of scientific ethics is involved and the matter should be cleared up not only in order to do justice to Perutz but also because of the influence that this episode may have on other people.”