Science: The Perils of Treading on Heredity

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The possibilities for gene therapy will be limited for the near future. If gene transplants are performed on tissue cells -- bone-marrow cells, for instance -- the altered genes will die with the patient; they cannot be passed on to any children the patient might subsequently have. Someday, however, it may be possible to change genes in germ cells, which give rise to sperm or eggs. If that feat is accomplished, the new genes would be transmitted to one generation after another.

That is what most frightens the foes of genetic engineering. If biologists can change the course of heredity, they can try to play God and influence human destiny. In 1983 activist Jeremy Rifkin, a longtime opponent of many kinds of genetic research, and several dozen theologians mounted an unsuccessful effort to persuade Congress to ban all experiments on human germ cells. Said Avery Post, president of the United Church of Christ, at the time: "We're not good enough or responsible enough. There is no question about it. We will abuse this power."

No geneticist is currently planning to transfer genes to human germ cells. Even though mankind has been playing God since biblical times, rearranging the germ lines of crops and farm animals to suit human needs, researchers do not advocate extending such genetic tinkering to people. But medical scientists have an obligation to protect humanity against disease and pestilence. Once it becomes possible to eradicate a gene that causes a fatal disorder, and thus keep it from passing to future generations, it will be criminal not to do so. As director of the Human Genome Project, James Watson contends that the research has a crucial humanitarian mission. Says he: "The object should not be to get genetic information per se, but to improve life through genetic information."

Fortunately, the most ardent supporters of genetic research are the first to admit the potential for abuse and see the need for ground rules. Many ethicists and scientists who have studied the issues agree on certain basic principles:

-- Individuals should not be required to submit to genetic testing against their will.

-- Information about people's genetic constitution should be used only to inform and never to harm.

-- The results of a genetic assay should be held in strict confidence.

-- Genetic engineering in humans should be used to treat diseases, not to foster genetic uniformity.

Knowledge is power, the saying goes. It can be dangerous, but it can just as easily be used wisely. "I do have faith," says Case Western's Murray. "Not that the judgment of people is always right, but that eventually we will preserve a good measure of fairness and justice. If we can absorb Copernicus and Galileo, if we can absorb Darwin and Freud, we can certainly absorb mapping the human genome."

One thing is certain: the genie cannot be put back into the bottle. Like atomic energy, genetic engineering is an irresistible force that will not be wished or legislated away. The task ahead is to channel that force into directions that save lives but preserve humanity's rich genetic heritage.