Next. Michael Crichton

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СКАЧАТЬ involving adult stem cells is for the most part not controversial. But there is another kind of stem cell, the embryonic stem cell, that is highly controversial. It is found in umbilical cord blood, or derived from young embryos. Embryonic stem cells are pluripotent, meaning they can develop into any kind of tissue. But the research is controversial because it involves the use of human embryos, which many people feel, for religious and other reasons, have the rights of human beings. This is an old debate not likely to be resolved soon.

      SCIENTISTS SEE A BAN ON RESEARCH

      The current American administration has said that embryonic stem cells can be taken from existing research lines, but not from new embryos. Scientists regard existing lines as inadequate, and thus view the ruling a de facto ban on research. That’s why they are going to private centers to carry out their research, without federal grants.

      But in the end, the real problem isn’t simply a lack of stem cells. It’s the fact that in order to produce therapeutic effects, scientists need each person to have his or her own pluripotent stem cells. This would allow us to regrow an organ, or to repair damage from injury or disease, or to undo paralysis. This represents the great dream. No one is able to perform these therapeutic miracles now. No one even has an inkling how it might be done. But it requires the cells.

      Now, for newborns, you can collect umbilical cord blood and freeze it, and people are doing that with their newborns. But what about adults? Where will we get pluripotent stem cells?

      That’s the big question.

      TOWARD THE THERAPEUTIC DREAM

      All we adults have left is adult stem cells, which can make only one kind of tissue. But what if there were a way to convert adult stem cells back into embryonic stem cells? Such a procedure would enable every adult to have a ready source of his or her own embryonic stem cells. That would make the therapeutic dream possible.

      Well, it turns out that you can reverse adult stem cells, but only if you insert them into an egg. Something within the egg unwinds the differentiation and converts the adult stem cell back into an embryonic stem cell. This is good news, but it is vastly more difficult to do with human cells. And if the method could be made to work in human beings, it would require an enormous supply of human egg cells. That makes the procedure controversial again.

      So scientists are looking for other ways to make adult cells pluripotent. It is a worldwide effort. A researcher in Shanghai has been injecting human stem cells into chicken eggs, with mixed results—while others cluck in disapproval. It’s not clear now whether such procedures will work.

      It’s equally unclear whether the stem cell dream—transplants without rejection, spinal cord injuries repaired, and so on—will come true. Advocates have made dishonest claims, and media speculation has been fantastical for years. People with serious illnesses have been led to believe a cure is just around the corner. Sadly, this is not true. Working therapeutic approaches lie many years in the future, perhaps decades. Many thoughtful scientists have said, in private, that we won’t know whether stem cell therapy will work until 2050. They point out that it took forty years from the time Watson and Crick decoded the gene until human gene therapy began.

      A SCANDAL SHOCKS THE WORLD

      It was in the context of feverish hope and hype that Korean biochemist Hwang Woo-Suk announced in 2004 that he had successfully created a human embryonic stem cell from an adult cell by somatic nuclear transfer—injection into a human egg. Hwang was a famous workaholic, spending eighteen hours a day, seven days a week, in the lab. Hwang’s exciting report was published in March 2005 in Science magazine. Researchers from around the world flocked to Korea. Human stem cell treatment seemed suddenly on the verge of reality. Hwang was a hero in Korea, and appointed to head a new World Stem Cell Hub, financed by the Korean government.

      But in November 2005, an American collaborator in Pittsburgh announced that he was ending his association with Hwang. And then one of Hwang’s co-workers revealed that Hwang had obtained eggs illegally, from women who worked in his lab.

      By December 2005, Seoul National University announced that Hwang’s cell lines were a fabrication, as were his papers in Science. Science retracted the papers. Hwang now faces criminal charges. There the matter stands.

      PERILS OF “MEDIA HYPE”

      “What lessons can be drawn from this?” asked Professor McKeown. “First, in a media-saturated world, persistent hype lends unwarranted credulity to the wildest claims. For years the media have touted stem cell research as the coming miracle. So when somebody announced that the miracle had arrived, he was believed. Does that imply there is a danger in media hype? You bet. Because not only does it raise cruel hopes among the ill, it affects scientists, too. They start to believe the miracle is around the corner—even though they should know better.

      “What can we do about media hype? It would stop in a week, if scientific institutions wanted that. They don’t. They love the hype. They know it brings grants. So that won’t change. Yale, Stanford, and Johns Hopkins promote hype just as much as Exxon or Ford. So do individual researchers at those institutions. And increasingly, researchers and universities are all commercially motivated, just like corporations. So whenever you hear a scientist claim that his statements have been exaggerated, or taken out of context, just ask him if he has written a letter of protest to the editor. Ninety-nine times out of a hundred, he hasn’t.

      “Next lesson: Peer review. All of Hwang’s papers in Science were peer-reviewed. If we ever needed evidence that peer review is an empty ritual, this episode provides it. Hwang made extraordinary claims. He did not provide extraordinary evidence. Many studies have shown that peer review does not improve the quality of scientific papers. Scientists themselves know it doesn’t work. Yet the public still regards it as a sign of quality, and says, ‘This paper was peer-reviewed,’ or ‘This paper was not peer-reviewed,’ as if that meant something. It doesn’t.

      “Next, the journals themselves. Where was the firm hand of the editor of Science? Remember that the journal Science is a big enterprise—115 people work on that magazine. Yet gross fraud, including photographs altered with Adobe Photoshop, were not detected. And Photoshop is widely known as a major tool of scientific fraud. Yet the magazine had no way to detect it.

      “Not that Science is unique in being fooled. Fraudulent research has been published in the New England Journal of Medicine, where authors withheld critical information about Vioxx heart attacks; in the Lancet, where a report about drugs and oral cancer was entirely fabricated—in that one, 250 people in the patient database had the same birth date! That might have been a clue. Medical fraud is more than a scandal, it’s a public health threat. Yet it continues.”

      THE COST OF FRAUD

      “The cost of such fraud is enormous,” McKeown said, “estimated at thirty billion dollars annually, probably three times that. Fraud in science is not rare, and it’s not limited to fringe players. The most respected researchers and institutions have been caught with faked data. Even Francis Collins, the head of NIH’s Human Genome Project, was listed as co-author on five faked papers that had to be withdrawn.

      “The ultimate lesson is that science isn’t special—at least not anymore. Maybe back when Einstein talked to Niels Bohr, and there were only a few dozen important workers in every field. But there are now three million researchers in America. It’s no longer a calling, it’s a career. Science is as corruptible a human activity as any other. Its practitioners aren’t saints, they’re human beings, and they do what human beings do—lie, cheat, steal from one another, sue, hide data, fake data, overstate their own importance, and denigrate opposing views unfairly. That’s human nature. It isn’t going СКАЧАТЬ