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Last Updated on May 5, 2015, by eNotes Editorial. Word Count: 2343

Structures of molecules do not ordinarily make the covers of Time,Newsweek, and other popular magazines, but deoxyribonucleic acid (DNA) did. Books about how molecular structures have been determined do not ordinarily become bestsellers, but James Watson’s The Double Helix: A Personal Account of the Discovery of the Structure of DNA(1968) did. In the first half of the twentieth century, the structures of such biological molecules as DNA played little or no role in the thinking of biologists, medical researchers, and ethicists. In the second half of the twentieth century the knowledge of how DNA is structured and functions helped to transform not only biology but also many other fields, from anthropology to zoology. Whether DNA solves most of the mysteries of life, as Watson believes, or whether Watson and other DNA enthusiasts exaggerate its importance, as some critics believe, both critics and enthusiasts agree that DNA research has created an illuminating body of knowledge with which to be reckoned.

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James Watson, an older and famous scientist, wrote this book with Andrew Berry, a young and relatively unknown scientist and science writer, to commemorate the fiftieth anniversary of the discovery of the double helix. This double authorship presents problems to readers and reviewers because the book is written with the personal pronoun “I” rather than “we.” Watson, a very busy man, had Berry research and write various chapters, which Watson then criticized, commented on, and rewrote. The book deals with a number of controversial issues, and Berry’s views did not always coincide with Watson’s, but the authors agreed to represent the book as Watson’s reflections on a half-century of DNA research.

In many ways Watson is an ideal person to supervise such an account, as he played pivotal roles in discovering the double helix, studying the role of ribonucleic acid (RNA) in the transfer of genetic information, elucidating the genetic code, and heading the early phase of the Human Genome Project, which later culminated in the detailed mapping of the genetic instructions that govern the development of every human being. Much of the material in DNA: The Secret Life has been written about before, by Watson and others. Nevertheless, this book has been advertised as “the first full account” of the DNA story, even though very little of the early history of DNA research is discussed. The primary focus is on the period of DNA history in which Watson was directly involved.

In his previous memoirs, The Double Helix and Genes, Girls, and Gamow: After the Double Helix (2001), Watson provoked controversy by frankly expressing his opinions on the quirks, faults, and shoddy work of his fellow scientists (as well as the women in their lives). Some of these candid assessments are sprinkled throughout this unabashedly personal view of the history of DNA, but there are also long sections that describe relevant scientific ideas, experiments, and discoveries in an impartial and evenhanded way.

After a brief survey of the pre-double helix history of genetics, the authors begin their story on February 28, 1953, when the double helical structure of DNA was first found. Ironically, this day was Linus Pauling’s birthday; a few years earlier, this great chemist had determined one of the basic structures of protein, which he called the alpha helix. His method of using chemical principles and model-building served as an inspiration for Watson and Crick, who, in a further irony, had little chemical knowledge between them. The double helix proved to be much more important than the alpha helix, because it revealed how hereditary information is stored and how life-forms are replicated. For Watson, his and Crick’s discovery solved the secret of life itself.

One of the major themes in DNA: The Secret of Life is the relationship between nature (the influence of genes) and nurture (the influence of the environment) in understanding the phenomena of life. Surprisingly for a person who would mature into a gene enthusiast, the young Watson argued for the importance of upbringing, education, and personal effort in creating a human life. He then believed that he could make himself into whatever he wanted to be. Though exposed to religious ideas in his youth, he “escaped” his Catholic upbringing to become an atheist, materialist, and reductionist who believed that science, not religion, was the way to understand the universe. For his critics, DNA is not the only way to understand human beings, but for Watson, human life is nothing but a concatenation of chemical reactions, and the double helix was important because it brought materialistic thinking into the center of life itself—the nucleus of every cell. For him, DNA is what makes humans conscious, creative, destructive, even moral.

The authors realize that such “DNA-philia” generates obstacles in a book intended for general audiences, particularly those readers familiar with the eugenics movement of the nineteenth and early twentieth centuries and the racist ideology of the Nazis. In 1968, when Watson assumed the directorship of Cold Spring Harbor Laboratory on the North Shore of Long Island, he realized that Charles Davenport, a eugenicist, had been his predecessor. Davenport had advocated negative eugenics, the use of techniques that prevented “genetically inferior” people from having children. His efforts influenced sterilization laws that were passed in several states (and declared constitutional by the Supreme Court) and that led to the sterilization of more than sixty thousand individuals. These laws impressed Adolf Hitler in Nazi Germany, whose racist ideology resulted in the Holocaust, the genocide of more than six million European Jews. Watson himself believes that racism is not a necessary concomitant of eugenics, because good genes can occur in any race. With caveats, he describes himself as a eugenicist, but his new eugenics is based on the knowledge of DNA’s structure and properties that he and others did so much to clarify.

In this book, Watson recounts his oft-told tale of the double helix’s discovery, though this time he is more appreciative of Rosalind Franklin’s contributions as a talented X-ray crystallographer. However, he remains critical of Pauling’s triple helix. Pauling, who liked neither Watson nor The Double Helix, felt that Watson never understood his model as a heuristic “artifact.” Eventually Pauling and many other scientists became admirers of Watson and Crick’s model, which provided an elegant mechanism for the replication of DNA. Once this unzipping mechanism had been experimentally verified, the next step was to understand how the information contained in the DNA molecule was able to be used in making the proteins necessary for life.

RNA turned out to be important in the process of transferring genetic information from the nucleus to the cytoplasm. Watson and many other scientists participated in discovering the role that messenger RNA plays in mediating between genes and the protein molecules they encode. Crick was the first to recognize the role of adaptor molecules, later called transfer RNA, in bringing amino acid to the RNA sites where assembly of the polypeptide chains of proteins took place. Many scientists were involved in cracking the genetic code, which was based on triplets of certain components of the DNA molecule. It was a redundant code, with more than one triplet for most of the amino acids.

Once the code had been figured out, scientists could start to make artificial DNA molecules. Molecular biologists cleverly mastered techniques for editing DNA by cutting it, pasting interesting segments into it, and then copying the result. These recombinant DNA technologies created controversy because artificial DNAs, when inserted into plant, animal, or human cells, had the potential for great harm as well as great good. Initially, Watson was sympathetic to the moratorium on certain kinds of recombinant DNA research, but he later felt that the dangers of this research had been exaggerated and that the moratorium had caused needless delays in the advancement of science.

Once the fears about biotechnology had been assuaged, DNA discoveries could once again proliferate, and this new knowledge resulted in potentially valuable commercial products. For example, Genentech and Biogen were companies founded to make such products as insulin for diabetics, who had been relying on hard-to-use animal insulins. Other companies made genetically modified crops. For example, bioengineers inserted a gene into the DNA of corn that produces a protein toxic to corn-eating insects. Critics, especially in Europe, claimed that these “Frankenfoods” posed dangers both to other insects and to humans, but Watson believes that these genetically modified crops are good for humans and the environment.

The human genome, the set of genetic instructions in human DNA, is a major theme in the final chapters of this book. Watson sees the mapping of the human genome as one of the most important results of DNA research, and as the first director of the National Center for Human Genome Research, he was intimately involved in the early development of the project. The money needed to determine the precise positions of genetic markers along all the human chromosomes was about three billion dollars, or, to give this sum a context, the cost of six space-shuttle launches.

The Human Genome Project was facilitated by the discovery of the polymerase chain reaction, which made the amplification of very small amounts of DNA possible. Improving sequencing machines accelerated the mapping process. Craig Venter, first at the National Institutes of Health (NIH) and later at The Institute for Genomic Research (TIGR), improved sequencing techniques, but he came into conflict with Watson over patenting DNA sequences without knowledge of their functions. According to Watson, his views of the patenting of genes led to his resignation from the Human Genome Project, but according to others, his resignation was due to a personality clash between himself and Bernardine Healy, the new director of NIH.

Conflicts also existed between the public NIH and the private companies that were involved in mapping the human genome. A rough draft of the human genome, the result of both public and private efforts, was announced in 2000, and a complete map was disclosed in 2003. The twenty-first century will be a time devoted to the complex task of interpreting what these approsimately 30,000 genes mean (a number much less than the expected 100,000). Another surprise was the percentage of places in the genome that actually encode for protein—less than 1 percent. This has led some gene mappers to describe the human genome as a desert sparsely speckled with genetic oases.

Even before the completion of the map of the human genome, DNA knowledge was proving its worth, especially with DNA fingerprinting, a technique that uses repeating DNA segments to characterize specific individuals. Paleoanthropologists have used this technique to understand human evolution and migrations. It has also been valuable in genealogical research, paternity testing, and establishing the innocence or guilt of accused rapists. Because of the potential benefits of this technique for society, Watson believes that every American should be legally bound to give DNA samples to the government, a law that his critics see as a step toward the world envisioned by the English writer George Orwell in Nineteen Eighty-Four (1949).

With the identification of genes for particular diseases, genetics has become part of clinical medicine. However, this genetic knowledge has created ethical dilemmas. For example, sickle cell anemia largely affects African Americans, and some ethicists fear that genetic tests could be a way to further stigmatize groups already suffering from discrimination. Watson, on the other hand, thinks that such fears have led to these tests being underused, with a consequent harm to society.

In the book’s coda, Watson returns to the theme of nature versus nurture and reiterates his conviction of the importance of genes in understanding human nature. He rebukes his liberal critics for denigrating researchers who have discovered that IQ discrepancies between racial groups are so large that environment alone fails to explain the gaps. Watson is also optimistic that the genetic underpinnings of human psychological and social behavior will be discovered. He agrees with his critics that society should try to improve human beings through education, but that “we cannot in good conscience ultimately limit ourselves to seeking remedies in nurture.”

For Watson, the central question for the future use of DNA knowledge is whether humans can be convinced to accept the power of genetics to improve their condition. He also disagrees with his religious critics who derive their moral knowledge from revelation in such books as the Bible, whereas he claims to have “an innate moral intuition” shaped by natural selection that has as its goal the social cohesion of human groups. He even goes so far as to say that DNA may well come to rival religious Scriptures as the keeper of not only scientific truth but moral truths as well.

Voltaire, the French humanist, once said that it was as impossible to argue with an enthusiast as it was to convince a lover of the faults of his mistress. Watson is obviously a DNA enthusiast, and his forays into the philosophical, ethical, and political ramifications of DNA should be read along with the books of trained historians of science, philosophers, and bioethicians. Scholars have found errors, both large and small, in his earlier books, and DNA: The Secret of Life is no exception. Nevertheless, those sections of the book—and they constitute a majority—that deal with the scientific discoveries that created modern molecular biology are extremely insightful and informative.

Discoveries emanating from DNA have deepened knowledge of the phenomena of life, and the authors of this book have provided a helpful manual to the new biology. On the other hand, most humanists and many scientists would probably agree that DNA, as important as it is, cannot serve as a guide to the meaning of life. Such metaphysical questions are beyond the power of DNA research to answer.

Review Sources

American Scientist 91, no. 4 (July/August, 2003): 354-358.

Booklist 99, no. 13 (March 1, 2003): 1107.

Kirkus Reviews 71, no. 5 (March 1, 2003): 372.

Library Journal 128, no. 6 (April 1, 2003): 125.

New Scientist 178 (April 26, 2003): 52.

New Statesman 132, no. 4633 (April 14, 2003): 48-50.

The New York Review of Books 50 (May 1, 2003): 39.

The New York Times, June 15, 2003, p. 11.

Publishers Weekly 250 (March 3, 2003): 64.

Science News 163, no. 19 (May 10, 2003): 303.

The Washington Post Book World, May 18, 2003, p. 10.

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