Cloning is a fledgling science whose practitioners are the Wright brothers of the field. But with every new breakthrough, such as this week's birth announcement of two cloned calves in Texas, comes the realization that cloning may be airborne quicker than anyone thought.
In Washington and around America's dinner tables, the next question is arising with fresh urgency: Should the cloning of humans be permanently banned, or is it the inevitable outcome of a centuries-long attempt to improve creation through science?
In some ways, the question raises moral and policy concerns that other scientific breakthroughs of the 20th century did not. Nuclear technology, developed with the blessing of the federal government, was regarded as a moral necessity related to national defense. Recombinant DNA research, which scientists voluntarily halted for a year, was questioned mainly as a possible harm to the local community.
Cloning, though, for all its potential medical benefits, conjures images of a soulless Brave New World where people are the objects of engineering. It also raises deeper questions at the crossroads of science, faith, human identity, and ethical norms.
"This is an issue for now," says Marcel LaFollette, a science-policy expert at George Washington University in Washington. "If the public doesn't consider cloning humans a concern, if institutions don't get involved, this process will go forward. We will wake up in 20 or 30 years and wonder what happened."
This week both the science and politics of cloning were thrust before the public eye:
* On Tuesday, US scientists announced that calves George and Charlie have joined Dolly the sheep in the growing pantheon of cloned farm animals. Massachusetts bioengineers James Robl and Steven Stice used an advanced genetic technique to produce the calves, the first in what the duo hopes will become a commercially successful herd of cows that will produce drugs in their milk for use by humans.
* The US Food and Drug Administration, in an effort to head off plans by Illinois physicist Richard Seed to clone a human embryo in 18 months, declared it illegal to clone humans without FDA approval. The FDA's move is seen as an alternative to a congressional bill, introduced by Rep. Vernon Ehlers (R) of Michigan, to ban human cloning and embryo research.
* America's leading society for reproductive medicine warned Tuesday that legislation to halt human cloning could hamper other kinds of scientific research.
Public opinion is currently opposed to outright cloning of humans. But the public has not been introduced to researchers' persuasive medical arguments that cloning could help to end diseases and genetic imperfections.
Still, cloning may have more momentum than government regulators realize. The question is: Is 20th-century science so powerful that it will sweep along, eventually finding a rationale for the cloning of people?
GENETIC scientists themselves have mixed opinions about how or whether to proceed - or even if human cloning is possible. At a meeting of the International Embryo Transfer Society this week in Boston, where news of the calf clones was released, many scientists were dubious about the prospects. In a formal meeting on whether to take a position on human cloning, the group tended to oppose it - though in private talks many scientists felt that research must continue to explore cloning's possible benefits.
The technical feasibility of cloning humans is itself uncertain. There's no consensus that the job could be accomplished using the techniques that produced the calves, in which scientists remove the nucleus of an egg and replace it with the nucleus from another cell.
"In terms of technology and doing the process, it is a small leap for science, not a large one," says Dr. Robl, one of the scientists who cloned the calves. "But the biology of the human embryo, that's still unknown. I don't know any of my colleagues who are serious about such a thing, though some do think about it."
Sheep and cows have an embryo and a genetic makeup that allows for relatively easy cloning. Yet in experiments, pigs do not have simple embryos, nor do, for example, mice.
An experiment to clone humans would require repeated efforts, with the possibility of many failures in "test" cases leading to success. Dolly the sheep took 277 tries, with a number of ugly mistakes, before a healthy and complete sheep was born. Experiments with humans could take between 100 and 1,000 tries, some geneticists speculate.
"In the laboratory, ... you are supposed to carry the research forward without any regard for questions of what is right and wrong," says Dr. LaFollette. "Yes, scientists are humans. But they are also trained to look clinically at their work and at least to try to put emotions and subjective criteria aside."
Large segments of the scientific community are comfortable with cloning. "It is just a kind of step inside ordinary science and isn't so different than having 'delayed action twins,' " says Peter Caws of George Washington University. "I don't see any great moral debate."
Yet ethicists and theologians who oppose human cloning are concerned about the very nature of the discussion. Calls for caution and even Clinton's request for a five-year hiatus may not be enough to stop lab research once it has started.
"People never go full steam ahead. Even scientists balk at the idea of 'if we can, we should.' People always want to be moving with a cautious yellow light," says Christian ethicist Gilbert Meilaender of Valparaiso University in Indiana. "Who can argue with 'sensible' caution? But in fact, this argument allows us to do what we want while telling ourselves we are proceeding with a good conscience. We can describe ourselves as moderates who are thinking through the moral questions, while at the same time never saying, 'Maybe we should put up a red light.' "