The Mysterious World of the Human Genome. Frank Ryan
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Each was a key ingredient, but how on earth did the whole thing assemble in a way that made sense?
An important clue must come from the X-ray diffraction patterns. That meant they needed the help of Maurice Wilkins and Rosalind Franklin – ‘Rosy’, as Watson referred to her in his autobiography – who were conducting X-ray analyses of DNA fibres at the King’s College London laboratory.
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Rosalind Elsie Franklin was born in London to a prosperous Jewish family in 1920. From an early age she showed both a brilliantly incisive mind and the stubbornness necessary to make a distinguished mark for herself. She also showed an aggressively combative side to her personality that might prove a mixed blessing in overcoming the prevailing prejudices against Jews in society, as well as against women being in higher education and the scientific workplace. It didn’t help that her father, who appeared to be a similarly combative character to his daughter, opposed her notion of a career in science. In her second year at Newnham College, Cambridge, he threatened to cut off her fees, urging that she switch to some practical application in support of the war effort. Only when he was dissuaded by her mother and aunt did he relent and allow her to continue her course.
Franklin studied physical chemistry, which involved lectures, extensive reading and laboratory experience in physics, chemistry and the mathematics that applied to these disciplines. One of the mandatory texts she read was Linus Pauling’s The Nature of the Chemical Bond.
The youthful Rosalind Franklin was disappointed when she ended up with a good second, and not a first, ‘bachelor’s’ degree in 1941. Even then, such was the lingering prejudice against female graduates in science that she was forced to wait in an unseemly uncertainty, one shared with all previous female graduates of Newnham, until her due qualification was formally granted, retrospectively, in 1947.
Like Francis Crick, Franklin was seconded to National Service during the Second World War, studying the density and porosity of coal for a PhD, in which she helped to classify different types of coal in terms of fuel efficiency. Post-war, she followed this up with a research stint working under the direction of Jacques Mering at the Laboratoire Central des Services Chimique de l’Etat, in Paris. Here, Mering introduced her to the world of X-ray crystallography which he used to study the structure of fibres, such as rayon. ‘With his high tartar cheekbones, green eyes and hair combed rakishly over his bald spot’, Franklin was surprised to discover that Mering was Jewish, as well as being ‘the archetypal seductive Frenchman’. The still youthful, and perhaps naïve, Rosalind Franklin appears to have fallen in love with Mering, who was already married, but whose wife was ‘nowhere in evidence’.
Brenda Maddox, one of Franklin’s biographers, would draw attention to the fact that Franklin’s most imaginative and productive research was conducted when she was teamed up with male scientists of Jewish background. Mering also appeared to be attracted to the trim, slender young woman, with the lustrous dark hair and glowing eyes. They would spend entire days and on into the evenings deep in discussion and argument over likely meanings of X-ray plates and atomic structures.
However, Franklin’s infatuation with Mering would be painfully halted when, in January 1951, she took up a post as research associate at King’s College London in the Medical Research Council Biophysics Unit, directed by John Turton Randall. Her appointment happened to coincide with a major post-war rebuilding within the department, designed to accommodate new ambitions within the nascent field of biophysics. The precise nature and purpose of her appointment has since become the subject of debate. In part some confusion has arisen because Randall changed the scope of her appointment in between first confirming it and Franklin taking up the post. She had initially agreed to carry out X-ray diffraction studies of proteins, but Randall wrote to her before she took up her appointment, suggesting that she change direction to the study of DNA. According to Maurice Wilkins, this was at his suggestion. Whether at Wilkins’ suggestion or Randall’s own idea, Franklin agreed. She was offered the assistance of a promising graduate student, Raymond Gosling, to work with. But there was an inherent problem with this new direction.
Wilkins, who was Deputy Director of the MRC Unit based at King’s College, was the same scientist who had first lit the fuse of inspiration for Watson in the 1950 Naples lecture. Wilkins had initiated the research into DNA in the department, but happened to be deputising once again for Randall in America at the time of Franklin’s appointment. Up to now Gosling had been working with Wilkins on DNA; even after his return from America, Randall failed to inform Wilkins about the terms he now proposed for Franklin’s job description. This led to what Franklin’s later research colleague, Aaron Klug, would describe as ‘an unfortunate ambiguity about the respective positions of Wilkins and Franklin, which later led to dissension between them and about the demarcation of the DNA research at King’s’.
This is a short quote from the typed letter from Randall to Franklin, specifying her working conditions:
… as far as the experimental X-ray effort is concerned there will be at the moment only yourself and Gosling, together with the temporary assistance of a graduate from Syracuse, Mrs. Heller …
While this clearly suggests that Franklin was expected to take on the X-ray diffraction work, the qualification ‘at the moment’ is too vague to interpret. But there is nothing in this letter to suggest that Franklin should ignore the work performed by Wilkins, or that she should refuse to collaborate with the rest of the department in her approach to the DNA problem.
Wilkins, working with Gosling, had initiated the X-ray diffraction studies on DNA in the department, and in particular obtaining the best resolution diffraction photographs that existed up to this date. They had demonstrated a key property of DNA – that it had a regular, crystal-like molecular structure. In Paris Franklin had learned, and improved upon, X-ray diffraction techniques for dealing with substances of limited order. But even Klug, an ardent supporter of Franklin, admitted that in relation to the work conducted by Franklin in Paris, ‘It is important to realise … Franklin gained no experience of such formal X-ray crystallography.’
Back in early 1950 Wilkins had complained of poor-quality X-ray apparatus that was not designed for the scrutiny of exquisitely fine fibres. At his suggestion, the department had purchased a new and better-quality X-ray tube to be set up in the basement, but it had lain there for a year or more unused while Wilkins was distracted by the multiple tasks that fell to a busy deputy director of the unit. On her arrival, Franklin, not unnaturally, believed that she was there to take over the DNA work as her personal project. However, the returning Wilkins expected that Franklin had been brought in as his collaborator, to take up the research from where he had already developed it. He would subsequently admit that he was unqualified to take the X-ray diffraction work further and needed exactly such a dedicated and qualified collaborator. ‘That’s why we hired Rosalind Franklin.’
Unfortunately, Franklin and Wilkins now disagreed as to her role. Even so, rancour was neither necessary nor inevitable between the two scientists, personally or scientifically. These difficulties, provoked by Randall’s vagueness, might have been readily overcome with goodwill on both sides, but Franklin, in the opinion of both her biographers, was not inclined to cooperate.
Much has been written about prejudicial attitudes to women in science at this time. In particular an American journalist, and personal friend of Franklin’s, Anne Sayre, would write a biography of her in which she suggested that King’s College was particularly unfriendly to female scientists, with Franklin struggling to assert her presence in a domain that was almost exclusively male. But when another American journalist, Horace Freeland Judson, looked into this claim, he discovered that of the 31 staff working at King’s at this time, eight were female, including some working in a senior position in Franklin’s unit. A second biography of Franklin, by Brenda Maddox, confirmed that women were, on the whole, well treated at King’s College. Crick made the same point in his biography – and Crick had come to know Franklin well in the years following the DNA discovery. Even in Sayle’s more trivial complaint – that the main dining room was exclusively forbidden to women, who were thus precluded from lunchtime conversation – is misleading. There were two dining rooms. One was limited to men, but this, in the main, was used by Anglican trainees. The main dining room, used