Destiny May Hinge on ‘Big Science’ and a Mere $5 Billion
“Big science” has both a good and a bad name. World War II’s Manhattan Project was probably the first effort that focused the attention of hundreds of scientists and a large sum of federal funds on a single problem--the development of a uranium fission bomb. It was infamous because it brought atomic weapons into the world, but famous because it worked, quickly and effectively.
Other “big science” projects in the realm of engineering include the dazzling achievement of putting people on the moon and the discredited boondoggle of a defensive nuclear shield in space. In the realm of more abstract science, we have had several generations of large-price-tag particle accelerators, of which the latest, the superconducting super collider, involves both the most-centralized and the most-expensive approach to basic research so far.
But all these projects, worthy and not, have involved physical science and engineering. Now for the first time we have “big science” in biology, and we ought to stand up and cheer. The project involves sequencing the human genome--discovering the sequential order and chemical structure of the strings of DNA that make us what we are. And there is simply no doubt it is worth the $3 billion to $5 billion that it is expected to cost. In fact, this price tag, much smaller than that for “Star Wars” research or for the super collider, is a cheap way to unravel our human destiny.
To say that genes form the blueprint of that destiny is not to say that nothing else matters; blueprints are not finished buildings, which depend on a lot else besides those two-dimensional plans. But they contain the information that directs the work of building. Genes, of course, are merely chemicals--most important, long chains of deoxyribonucleic acid, or DNA. These spiraling chains are made of links called bases; four different kinds rearranged in vast numbers of ways provide a range of possible sequences that for practical purposes is endless.
The human genome has about 3 billion bases, or base pairs. They are organized into 46 chromosomes, and there are an estimated 100,000 genes spread along these chromosomes. Large chunks of the genome appear to be irrelevant--redundant, nonfunctioning, or even random sequences. But all the meaningful genes are buried among those strings of noise; and the genes go a long way toward making us who we are.
In 1986, leading molecular biologists such as James Watson, the co-discoverer in the early ‘50s of the double-helical structure of DNA, and Walter Gilbert, who helped develop a key method for DNA sequencing in the late ‘70s, supported the concept of sequencing the genome. They argued persuasively that while a focused search for specific, disease-causing the genes was needed, it would be inherently limited and in the end much more expensive than a comprehensive map of all the human genes and their sequences.
In addition, the map would generate thousands of new questions about human biology, normal and abnormal, and the answers to those questions would tell us enormous amounts about how the human body--and mind--are built, from scratch.
The eventual opportunity for prediction and control over that body, that mind, would be staggering. Along the way, partial solutions to some of the thousands of diseases known to be caused in part by the actions of single defective genes--sickle-cell anemia, thalassemia, Tay-Sachs disease, possibly Alzheimer’s disease--would start to spin off from the genome project. When we consider that locating the gene that causes cystic fibrosis cost between $50 million and $200 million and took almost a decade, the genome project starts to look like a bargain at $3 billion to $5 billion.
But there is more to this than pinning down disease-causing genes, or even unraveling the mysteries of basic, normal human biology. (Why does the heart have four chambers? How does collagen get built into skin? Where do the enzymes that govern brain chemistry come from?) Beyond all this is the fundamental issue of control of these human processes.
To see the implications, consider the parallel projects, already under way, designed to sequence the genomes of cows, pigs, sheep and chickens, to say nothing of corn and tomatoes. Private corporations want to make leaner beef, or cattle more resistant to the tsetse fly in Africa, or pigs that produce 20 piglets per litter, like the Chinese pig, but pork that tastes as good as ours.
The obvious implication is that sequencing the human genome will make it equally possible to make a better human. The hope is that no one will be tempted, at least not in the sense that they are with domestic animals. But what is the goal of eliminating cystic fibrosis and sickle-cell anemia, if not in some sense to make a better human?
Even within the realm of disease we have to consider the downside of eliminating something from the genome. Manic-depressive illness, for instance, a disorder of mood swings and crazy thoughts, is known to be linked to some types of creativity. Who knows what we will eliminate if we manage to change that gene? In more complex realms, such as the genetics of intelligence, personality, attractiveness, strength, and skill--well, you get the idea. Once we know how these things are influenced by certain genes, the temptation to play God will be great.
I don’t have any answers. Some leaders of the human genome project have formally recognized the importance of such questions by proposing to devote at least 3% of the project’s funds to exploring the ethical and social implications of the new knowledge. That would seem a minimum.
We have embarked on one of the most exciting adventures in the history of science, one that will change our view of ourselves as much as the discoveries of Copernicus, Darwin and Freud did. We all need to be thinking very carefully about what this knowledge will mean, and what we will do with it when we have it.
