It was supposed to be a simple bargain--an honest if somewhat bizarre deal struck between one of the last Stone Age peoples and the most technologically advanced society.

Soon after the Hagahai emerged from the cloud forests of Papua New Guinea in the late 1980s and made their first contact with the outside world, anthropologists stumbled across a remarkable secret flowing in the tribesmen's blood.

The Hagahai, who have harvested yams and hunted wild boar along the remote Yuat River for millenniums, carried a rare virus in their white blood cells. It was a pathogen similar to ones that cause leukemia, but it did not harm the tribesmen.

American scientists wanted to understand why, so they made the tribe a quiet offer: Let the U.S. government patent their cells in exchange for half of the royalties from any breakthroughs in leukemia research derived from their blood.

The Hagahai, who by then were familiar with money, agreed. After donating a few test tubes of blood to the National Institutes of Health in Bethesda, Md., they promptly went back to stalking wild game.

If the story of U.S. Patent No. 5,397,696--for a DNA sequence dubbed "Papua New Guinea human T-lymphotropic virus (PNG-1)"--had ended there, it probably wouldn't rank as a footnote in the dazzling saga of the genetic revolution in the 1990s.

But the tale of the 1995 Hagahai patent and its bitter aftermath is far from forgotten in scientific circles. Instead, it has become the defining morality fable for one of the most intriguing and highly controversial new frontiers in human biology: the hunt for genetic cures in the DNA of small ethnic groups.

Buoyed by technical advances that make massive DNA testing economically feasible and spurred by the realization that humanity's genetic diversity is yielding to cultural assimilation day by day, researchers are scrambling to the most secluded corners of the Earth, hoping to tap the "healthy genes" embedded in the nuclei of the Cherokee, the Amish, Solomon Islanders, the Hagahai and others.

Click to see map of genetic research projects around the world

So far, the strange quest has fired the imagination of individual academic researchers and big biomedical companies. Probably the most compelling proposal on the horizon is the Human Genome Diversity Project, a plan put forth by a loose coalition of international geneticists to collect and preserve the DNA from 400 human populations and ethnic groups.

If funding is approved by Congress after a recommendation by the National Academy of Sciences, the diversity project could officially begin gene sampling this year, adding to a store of samples collected without government involvement.

"We've always known the strength of any species lies in its diversity," said Victor McKusick, a pioneering population geneticist at Johns Hopkins University who supports the global DNA-sampling effort. "Now, we're finally beginning to put those differences to useful work. These are truly exciting times."

To some, the case of the Hagahai genes proves otherwise.

When news of the New Guinea patent spread, howls of outrage sounded from human-rights groups.

Is human tissue, they asked, just another natural resource like timber or gold? If so, what government has the right to poach on a foreign country's genetic heritage?

Charges of "biopiracy" echoed in news reports across the Pacific. News releases declared that the United States had done the unthinkable and "patented itself a foreign citizen." Rattled by the publicity, Papua New Guinean officials summoned the U.S. ambassador for an explanation. The anthropologist who brokered the deal was hauled off a flight at Port Moresby, the Papua New Guinean capital, and interrogated like a spy.

What the Hagahai made of the fracas is not recorded. The NIH, however, was stunned: Though the blood still remains frozen in its freezers, it quietly dropped its claim on the intellectual property rights to the tribesmen's cells and the research is largely dormant.