Cracking the Genome: Inside the Race to Unlock Human DNA (review)

Kevin Davies, editor of Nature Genetics, is captivated by genetics. Like the reporters in the early days of space launches, he conveys in Cracking the Genome his overwhelming excitement: his purpose is "to capture the excitement, intrigue, mystery, and majesty of the quest for biology's holy grail" (p. 9). Except for the race to outer space, no other area of science and technology has enjoyed such media hype. NASA had a comfortable partnership with the press—until the Challenger crashed in January 1986; the race to inner space, to unlock human DNA, enjoys a similar relationship with a press that amplifies promises and contributes to hype. Davies portrays genetics research as a war, a clash of ideologies and strategies involving "regiments" of machinery, "corps" of biologists, "genetic age gladiators," "troops" to be rallied, and an occasional "fragile truce." He is a lively writer, communicating scientific material in an accessible style and turning the competition between the NIH and Craig Venter into a dramatic and daring adventure.

Davies believes that genomics will forever change our lives through its revolutionary impact on medicine and society. We will be able to identify, diagnose, and treat virtually every human disease and to understand the genetic components of human behavior. Physicians will screen our genomes to produce personalized scorecards of risks and recommend effective treatments. No need to visit a doctor: just take a cheek swab and mail it in for DNA diagnostics; you will learn your likelihood of developing most diseases and even complex behavioral conditions. Clinics will then be able to select genetic traits in human embryos and replace or repair faulty genes. Our children will be diagnosed and treated for diseases they have not even developed. We will be able to engineer traits into the genetic material "as easily as sewing a button on a shirt": "We are on the brink of a new era in which individuals will be diagnosed and treated based on their genome, not their symptoms" (p. 217). But will people also be incarcerated on the basis of genetic predictions before they actually commit crimes?

The author is a biological determinist. Quoting the concluding message of the film GATTACA—"there is no gene for the human spirit"—Davies comments: "Whether that will remain the case . . . remains to be seen" (p. 235). I found little in his book of the skepticism, the critical perspective that one hopes to see in journalism. Images of God figure prominently in his descriptions—but a chapter on "the language of God" pervading genetic discourse ignores religious objections to gene "tampering" and the fact that the project is at war, not just with competing scientists, but with religious groups. Similarly, Davies shows limited vision in his enthusiasm about the discovery that we are all genetically similar, that there is no scientific basis for racial categories: what does it mean to say that we are genetically alike in the cultural context of persistent racism?

Will genetics change clinical medicine? At least some knowledgeable people have doubts. Neil Holtzman from Johns Hopkins points to the complexity of many disorders as genes interact with environmental factors including smoking, pollution, and diet. He believes that "the new genetics will not revolutionize the way common diseases are identified or prevented."¹ Anthropologists point to culture as yet another strand in the complexity of interaction between biology, genes, and environment. Reality is far too complex for an easy integration of genetics into medical practice. Moreover, tests that reveal probabilistic predictions of diseases for which there are no cures, are not so valuable to patients. Davies reports that Venter, after having his DNA sequenced, started taking anticholesterol medicine. But does one need a DNA test for that?

Medicines can be targeted to our specific genetic make-up, but will pharmaceutical companies...