Professor Maurice Wilkins

Biophysicist who shared the Nobel Prize with Crick and Watson for his X-ray work on DNA
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The Independent Online

Maurice Hugh Frederick Wilkins, molecular biologist: born Pongaroa, New Zealand 15 December 1916; Deputy Director, Medical Research Council Biophysics Unit, King's College, London University 1955-70, Lecturer, Biophysics 1958-63, Professor of Molecular Biology 1963-70, Director 1970-72, 1974-80, Professor of Biophysics 1970-81 (Emeritus), Fellow 1973-2004; FRS 1959; Nobel Prize in Physiology or Medicine (jointly) 1962; CBE 1963; married 1959 Pat Chidgey (two sons, two daughters); died London 5 October 2004.

The discovery of the double-helical structure of deoxyribonucleic acid (DNA) in 1953 is widely regarded as the most significant discovery in biology of the 20th century. The 1962 Nobel Prize for Medicine was awarded jointly to Francis Crick and James Watson, working in the Cavendish Laboratory in Cambridge, who proposed the model, and Maurice Wilkins who, with Rosalind Franklin and colleagues at King's College London, had recorded X-ray diffraction data on which the model was based.

The claim by Oswald Avery in 1944, working at the Rockefeller Institute in New York, that DNA was the molecule that carried the genetic information had been received with scepticism. Wilkins recalls that while he and Crick, firm friends from the late 1940s, were sitting in the Embankment Gardens outside King's, Crick offered the view that Wilkins was wasting his time working on DNA and couldn't understand why he didn't concentrate on something useful, such as proteins. It is a mark of Wilkins' insight that he resisted this advice and that, by 1950, he was persuaded not only that DNA was the genetic material, but that X-ray fibre diffraction offered the most promising way of obtaining clues to how it functioned by determining its three-dimensional structure.

As early as 1950, Wilkins assembled a parallel array of uniform, thin fibres (each a fraction of a millimetre in diameter) drawn from a DNA gel. The diffraction pattern from this specimen, taken with Raymond Gosling, was what so excited James Watson when Wilkins showed it at a conference in Naples in the spring of 1951. Watson, in his account of this event in The Double Helix (1968), wrote,

Maurice's X-ray diffraction pattern of DNA was to the point. It was flicked on the screen near the end of his talk. Maurice's dry English form did not permit enthusiasm as he stated that the picture showed much more detail than previous pictures and could, in fact, be considered as arising from a crystalline substance. And when the structure of DNA was known, we might be in a better position to understand how genes work.

This regularity in the coding of the genetic information in chemical structure implied by this data is a crucial feature of the double helix and is central to the biochemical processes which have evolved for copying the information and translating it into the structure of the proteins that give organisms their distinguishing characteristics. The fact that these processes are independent of the particular message being read, with essentially the same mechanisms for processing information being employed in all organisms, is inextricably linked to an understanding of Darwinian evolution and is central to technologies for the manipulation of DNA in the development of new drugs and genetically modified organisms.

Much has been written on the relationships between the principal protagonists in the discovery of the double helix and also between the two laboratories in which they worked. Crick, Franklin, Watson and Wilkins have all endured hostile criticism and snide disparagement of their roles in the story. Much of this comment is ill-based, ignoring the well-researched account in Robert Olby's The Path to the Double Helix (1974). Fortunately, we now also have Maurice Wilkins' own highly reflective account in his autobiography The Third Man of the Double Helix, published in 2003. Taken together, these accounts give a balanced view of the relationship between the London and Cambridge laboratories.

While there was opportunism in the way X-ray results from King's were exploited in the Cavendish, it is important to emphasise that the traffic of ideas was not all one-way. Watson and Crick not only encouraged the King's group to begin the molecular model-building that subsequently was crucial in their discovery of the double helix, but also provided them with the workshop jigs for fabricating atomic components.

Within the King's laboratory, it is clear from these accounts that both Wilkins and Franklin were victims of decisions by the head of department, J.T. (later Sir John) Randall, acting, in Wilkins words, "in Napoleonic style". Franklin, following her recruitment from a Paris laboratory early in 1951, was misled about the degree of independence she would have in the X-ray work on DNA; Wilkins, on returning from holiday, found himself sidelined from a project on which he and Gosling had made important contributions. The resulting tension lasted throughout the two years that Franklin was at King's, and led to two groups working on the same project with essentially no collaboration between them.

In fairness to Randall, it was his enormous energy and vision that had secured the funding which had allowed the pioneering biophysics laboratory at King's to be established in the first place and he was inevitably under great pressure to deliver. It is most unfortunate that, on this occasion, the exercise of his management style proved to be so seriously counter-productive.

Wilkins was an outstanding experimentalist whose approach to the analysis of X-ray diffraction patterns from DNA fibres benefited greatly from his earlier work on the development of new types of microscope. His approach focused on the overall variation in diffracted intensity across the pattern rather than on the particular points in the pattern where this variation was sampled. He was aided by Alex Stokes, a colleague at King's who, at an early stage in the X-ray work, recognised that the observed overall intensity distribution indicated that DNA had a helical shape. Stokes, responding to a request from Wilkins, famously on the train home, derived the complicated mathematical expression that allowed the X-ray diffraction from an array of helical molecules to be calculated.

Franklin, through the development of improved methods of controlling the water content of the fibres, obtained better defined diffraction patterns of both of the two types of diffraction previously obtained from a variety of DNAs by Wilkins and his colleagues. These two patterns were designated "A" and "B" and crucially Franklin and Gosling were able to induce a transition between the two forms by varying the relative humidity of the fibre environment.

In the division of responsibilities for the DNA programme, it had been agreed that Franklin should work with the DNA sample originally provided to Wilkins by the Swiss biochemist Rudolph Signer. None of the other samples available to the King's laboratory gave such well-defined diffraction patterns as those obtained from this DNA by Franklin and Gosling. Much to the surprise of Herbert Wilson, who had now joined Wilkins' group, Wilkins felt unable to ask for a share of the Signer DNA.

The tragedy for the progress of the DNA work at King's was that the best diffraction data was in the hands of the group who - it turned out - made wrong choices in deciding how best to analyse the data, leading during a crucial period in 1952 to a militant dismissal by Franklin of the possibility that DNA was helical. Franklin opted to work on the A pattern employing methodologies derived from those used in the study of single crystals, rather than an approach based on Stoke's analysis. She also emphatically rejected using molecular model building methods that had been so successful in elucidating the structure of fibrous proteins.

The famous B pattern (pattern 51) recorded by Franklin and Gosling in May 1952 was not seen by Wilkins until January 1953 when, with Franklin moving to join J.D. Bernal in the Physics Department at Birkbeck College, it was handed to him by Gosling, without any restrictions on its use. This was the pattern shown by Wilkins to James Watson on a visit to King's at the end of January 1953.

Back at Cambridge, Watson's memory of the details of the pattern was limited. However, when taken together with the X-ray diffraction data from patterns recorded by the Wilkins' group (from a variety of DNAs and also from sperm heads) previously given to Crick, and crucially with Crick's recognition that the symmetry of the A form determined by Franklin and Gosling implied a double helix with DNA strands running in opposite directions, it was sufficient with only a few weeks model building to define the general features of their structure for DNA.

In their presentations of the double-helical model for DNA, Watson and Crick emphasised the importance of further detailed X-ray diffraction analysis to confirm that what was an extremely attractive model was indeed correct. A major part of Wilkins scientific achievement was his painstaking work with colleagues over the next decade to achieve this. This involved the development of both experimental and analytical techniques which took advantage of new technological developments and in particular the increasing availability of high-speed digital computers. Once the double helix was on a secure footing, Wilkins and his colleagues applied with great success the techniques they had developed in the study of DNA to characterise a variety of other biological structures including ribonucleic acids, complexes of DNA with proteins and nerve membranes.

At first meeting Wilkins often appeared shy. He rarely turned up in the laboratory in other than a grey suit. He tended to speak slowly, in an undemonstrative style. However, closer acquaintance revealed a wry sense of humour and a warm and considerate personality. He was exceptionally generous with his ideas and results, being strongly committed to the view that science was a co-operative activity.

Wilkins' association with J.T. Randall dated from 1938 when he joined him as a PhD student at Birmingham University to work on luminescence of solids. This was followed by war work on the vaporisation of uranium metal, first in Birmingham and then as part of the Manhattan Project in California. After the war, Wilkins decided that his future research would be in biology and he rejoined Randall, briefly at St Andrews and then in 1946 at King's College London where, within the Physics Department, a unique Biophysics Research Unit employing biologists, physicists and chemists was established with support from the Medical Research Council.

Wilkins was Randall's right-hand man, serving as Deputy Director of the unit, and in 1970 succeeding him as Director. In these posts he carried a large administrative load, earning respect for his integrity and fairness. He was held in particular affection by porters and technical staff for the genuine interest he took in their work and their lives, being widely referred to as "Uncle".

Maurice Wilkins was born in Pongaroa, New Zealand in 1916 where his father had recently moved from Dublin to work as a doctor. Back in England, Maurice attended King Edward's School, Birmingham, and developed skills in making equipment, particularly telescopes, in a workshop built for him by his father. He studied Natural Sciences at St John's College, Cambridge, and was much influenced by the Cambridge Scientists' Anti-War Group and by J.D. Bernal's use of X-ray diffraction to study the structure of proteins and viruses.

Wilkins had little appetite for academic or scientific politics. But he never lost his concern for the social impact of science, and pioneered rigorous undergraduate courses on the subject. He served as president of the British Society for Responsibility in Science, from 1969 to 1991. He was also an active participant in Pugwash, an organisation dedicated to preventing nuclear war.

Wilkins had longstanding interests in the arts. His autobiography includes a self-portrait drawn during his time in Cambridge and he met his wife Pat through the Institute of Contemporary Arts. His welcoming approach resulted in many contacts, particularly from artists interested in links between science and art. Many of these visits - like that of the composer Stockhausen - were stimulated by an interest in helical structures. A Leverhulme grant enabled a young art student to spend time in the King's laboratory collecting material for a book on spirals in science and art.

Despite a minor cerebral haemorrhage in 2003, he was well enough to play an active role in the 50th anniversary celebrations of the discovery of the DNA double helix at King's College. His enthusiasm for making things never left him and he was busy constructing bookshelves when he suffered another haemorrhage; he died a few days later with his wife and four children at his bedside.

Watson Fuller