But a feeling of ownership doesn't hold up in court. And at this point, the law isn't clear on whether you have the right to own and control your tissues. When they're part of your body, they're clearly yours. Once they're excised, things get murky.

The scale of tissue research is only getting bigger. "It used to be, some researcher in Florida had 60 samples in his freezer, then another guy in Utah had some in his," says Kathy Hudson, a molecular biologist who directs the Genetics and Public Policy Center at Johns Hopkins University. "Now we're talking about a massive, massive scale." Within the last year, the National Cancer Institute started gathering what it expects will be millions of tissue samples for mapping cancer genes; the Genographic Project began doing the same to map human migration patterns, as did the N.I.H. to track disease genes.

Many scientists depend on access to tissues without the burden of restrictions that donors might make. (Restrictions like, You can use my tissues for this research, not that research; don't commercialize them, or do, and give me a cut.) At this point, scientists largely have the access they want. And they hope to keep it that way for fear that restrictions might slow research. But a growing number of activists -- ethicists, lawyers, doctors and patients -- are arguing cases and pushing for federal regulations that would change the status quo by granting people rights to control their tissues. These days, their attention is focused on a potentially landmark court case: Washington University is claiming ownership of tissues from 6,000 patients who want their samples removed from the university's prostate-cancer bank. Hudson, who has conducted focus groups about the public's feelings on the tissue issue, says she believes that tissue rights have the potential to become a bona fide movement. "I could see a broader mobilization where people start saying, 'No, you can't take my tissues,"' she told me. "All I can say is, we better deal with the problems now instead of waiting until that happens."

Anna O'Connell agrees. The day I visited her lab, she rolled a vial of Ted Slavin's serum in her hand. We sat as she told me she wanted to see this issue settled, but she wanted to make one thing clear: scientists aren't out to deceive people about their tissues. "We genuinely want to gather as much information as we can to advance research," she said. "The problem is, in all that excitement, sometimes scientists don't think about consequences."

The $3 Billion Man

The tissue rights debate began in 1976, with a man named John Moore. He worked 12-hour days, 7 days a week, as a surveyor on the Alaska pipeline. He thought it was killing him. His gums bled; his belly swelled; bruises covered his body. It turned out that he had hairy-cell leukemia, a rare cancer that filled his spleen with malignant blood cells until it bulged like an overfilled inner tube. Moore found David Golde, a prominent cancer researcher at U.C.L.A., who said that removing his spleen was the only way to go. As Moore told it to the courts and the media, he signed a consent form saying that the hospital could "dispose of any severed tissue or member by cremation." A normal spleen weighs less than a pound; Moore's weighed 22. After the surgery, at the age of 31, Moore moved to Seattle, became an oyster salesman, went on with his life. But every few months, he flew to Los Angeles for follow-up exams with Golde.

At first, Moore didn't think much of the trips. But after a few years of flying from Seattle to L.A. so that Golde could take bone marrow, blood and semen, Moore started thinking, Can't a doctor in Seattle do this? When Moore asked Golde about doing his follow-ups in Seattle, Golde offered to pay for the plane tickets and put him up in style at the ritzy Beverly Wilshire. Moore didn't start getting suspicious until one day in 1983 -- seven years after his surgery -- when a nurse handed him a consent form that said, "I (do, do not) voluntarily grant to the University of California all rights I, or my heirs, may have in any cell line or any other potential product which might be developed from the blood and/or bone marrow obtained from me." At first, Moore circled "do."

"It's, like, you don't want to rock the boat," Moore told Discover magazine years later. "You think maybe this guy will cut you off, and you're going to die or something." But when the nurse gave him an identical form during his next visit, Moore asked whether Golde was doing something commercial with his tissues. According to Moore, Golde said that U.C.L.A. would never do such a thing. But Moore circled "do not," just in case. That's when Golde started calling, saying: You must have accidentally mis-signed the consent form. Come back and sign again. "I didn't feel comfortable confronting him," Moore said later, "so I said, 'Gee, Doctor, I don't know how I could have made that mistake."' But he didn't go back and sign.