Then Zeus transfers each precious droplet to a nearby sheet of nylon, moistens a designated spot and pivots back to the glass plates to find the next sample on its list. When Zeus is done, the nylon sheet will be spotted with a grid of about 1,000 droplets, forming what researchers call a microarray. Once the machine has created a few dozen of these arrays, they will be rolled up, inserted into glass tubes and doused with radioactive dye and genetic material from a range of human tissue types - from normal, healthy cells to diseased cells representing breast, prostate, lung or colon cancer. Emerging from this experiment will be a set of data points, glowing with eerie phosphorescence, that may someday lead scientists to a new cure for one of the deadliest scourges known to man.

When the human genome was sequenced last year, scientists finally gained access to the full text of God's reference manual: the 3 billion biochemical "letters" that spell out our tens of thousands of genes. These genes, strung out along the 46 chromosomes in virtually every human cell, carry the instructions for making all the tissues, organs, hormones and enzymes in our body.

Once scientists have decoded these instructions - a process already well under way - they should have a better understanding of precisely what happens, down to the molecules within individual cells, when the body malfunctions. And, says Francis Collins, director of the National Institutes of Health's Human Genome Research Institute, "if you understand the genetic basis of a disease, then you can predict what protein it produces and set about developing a drug to block it."

Here in Cambridge, a new industry is quietly taking shape that proposes to do that on a grand scale, as companies with names like Biogen, Genzyme, Genetics Institute and Millennium Pharmaceuticals - Zeus' home - prepare to change forever the way doctors fight disease. They're not alone: spurred by the prospect of scientific glory and enormous profit, big pharmaceutical firms and university and government labs have been joined by scores of new companies, not just in Cambridge but in Montgomery County, Md., Silicon Valley and other high-tech hot spots around the nation. It's a virtual gold rush to mine the mountain of potentially valuable data the genome contains.

The result could be a medical revolution. Until now, doctors haven't actually been fighting illnesses like cancer, stroke and heart disease. Instead they've been intervening at the level of symptoms - the last, visible step in a complex cascade of biochemical events. And they have done it largely by trial and error - finding new medicines in exotic plant extracts, for example, or looking for chemical compounds that resemble existing drugs. The process is so woefully inefficient that the drugs currently available target only 500 or so different proteins in the body, out of the 30,000 or so we're made of. Says Collins: "We've beaten those targets to death."

Even when they have the drugs in hand, doctors have to guess which ones might work for a given patient. To treat high blood pressure, for example, physicians must choose from six different classes of medications - and it's the rare patient who hasn't had to work his or her way through several of them before finding a medicine that works.

But in the new era of genomic medicine, this halting, inefficient approach should give way to something much more rational and systematic. Doctors will treat diseases like cancer and diabetes before the symptoms even begin, using medications that boost or counteract the effects of individual proteins with exquisite precision, attacking sick cells while leaving healthy cells alone, and they will know right from the start how to select the best medicine to suit each patient. MORE>>

PAGE 1 | 2 | 3 | 4