A common ground to discuss genetics

The Century of the Gene
Evelyn Fox Keller
Harvard University Press 2000
192 pp., $22.95

When Steven Spielberg filmed Jurassic Park, he hired paleontologist Jack Horner as his science advisor. Horner had spent much of his life trying to correct the popular image of dinosaurs as marauding predators. He reminded us that the 12,000-pound Tyrannosaurus rex could not run, see much beyond its nose or grasp prey between its front claws (its arms were too short). It did, however, have a keen sense of smell and probably sought rotting carcasses for food.

But when Spielberg created the ultimate movie moment in Jurassic Park—with the T. rex pursuing Ellie and Ian in their Jeep—good science gave way to theater.

'The most egregious problem'
Evelyn Fox Keller, professor of history and philosophy of science at Massachusetts Institute of Technology, uses this analogy to describe our current ideas about genetics. The popular image of the T. rex led Spielberg to "lapse into established stereotype," thereby "extending the life of the mythical T. rex." Today's genetic scientists also are extending the popular image of the gene as the one thing that constitutes "the basis of all aspects of organismic life," despite the fact that current science no longer supports such a view.

In fact, Keller says the central premise in Jurassic Park—that one could clone a dinosaur from its DNA—is the "most egregious problem" in how we perceive the science of genetics. This misperception reveals our continued homage to an early (and flawed) view of genes. Yet such absurd images persist, despite the fact that leading edge science makes such a proposition an "utterly fantastic premise."

According to Keller, the term "genetics" was coined in 1906. The term "gene" was used in a biological context three years later, although no one could define it. By 1933, "gene" had become "the biological analogue of the molecules and atoms of physical science," still without any scientific basis. Not until 1943 with the "identification of DNA as the carrier of biological specificity in bacteria" did we begin to answer the question, "What are genes made of?" It was Watson and Crick's famous announcement in 1953 that "convinced biologists not only that genes are real molecules, but also that they are constituted of nothing more mysterious than deoxyribonucleic acid" (now known simply as DNA).

A new understanding of genetics
This image of genetics captured the imagination of scientists and non-scientists alike. The "one gene/one enzyme" hypothesis has transformed the way we see the world. Both scientists and the media almost daily besiege us with images of curing incurable diseases, creating fantastic new organisms and "feeding the world"—all by the simple manipulation of a few genes.

Keller points out that while the rhetoric continues to make fantastic claims, the science of genetics points in a different direction. Hieter and Boguski have described the new direction best with the term, functional genomics, defined as "the development and application of global (genome-wide or system-wide) experimental approaches to assess gene function by making use of the information and reagents provided by structural genomics." In other words, the real benefit of genetics seems to be derived not from the manipulation of a few genes, but from our enhanced understanding of how nature works.

Keller describes this profound shift in thinking:

For almost fifty years, we lulled ourselves into believing that, in discovering the molecular basis of genetic information, we had found the 'secret of life;' we were confident that if we could only decode the message in DNA's sequence of nucleotides, we would understand the 'program' that makes an organism what it is.

But the new view of genetics has more to do with how we think about biological organization than with how we modify it. As we enter the 21st century, Keller says we are at a "rare and wonderful moment" when the greatest insight we might gain from the study of genetics is humility.

These insights provide fruitful common ground for creative dialog between geneticists and advocates of sustainable agriculture—groups that have had very different world views. Twentieth-century geneticists claim to have discovered "the secret of life" and a means to recreate a world that suits the needs of the human species. On the other hand, scholars of sustainable agriculture have sought to understand how natural systems work and how to fit human enterprises into that system.

Changing vs. understanding
As a result, there has been little room for interaction. Geneticists focused on changing "the critical elements of the biological blueprints at will" while sustainable agriculturists were intent on understanding the biological blueprint and (as Aldo Leopold would have put it) discovering how to effectively be part of that rich biotic community.

The new genetics, with its emphasis on better understanding how complex biological systems work, provides an enormous opportunity for enriching both the study of genomics and the study of ecology. The future of agriculture certainly would benefit from such a dialog, and Keller's book is a good place to start. -- Fred Kirschenmann