It is wrong and "demeaning to human nature" for government to try to stop or limit human cloning experiments, said Sen. Tom Harkin, (D- Iowa).
"Human cloning will take place and it will take place within my lifetime," he said. "I think it is right and proper. ... It holds untold benefits for humankind in the future."
Harkin, who lost two sisters to cancer, has been one of the strongest supporters on Capitol Hill of medical research. The senator was instrumental in starting a new Office of Alternative Medicine at the National Institutes of Health and is co-author of a plan to increase NIH funding this year by $5 billion.
Ian Wilmut of the Roslin Institute in Edinburgh, Scotland, said that since the world learned he and colleagues had cloned an adult sheep named Dolly, there has been an explosion of speculation about cloning of humans.
But Wilmut said human cloning is not practical, possible or ethical. "Similar experiments with humans would be totally unacceptable," he said.
"I don't see any reason why we would want to copy a person," said the scientist. "I personally have still not heard of a potential use of this technique to produce a new person that I would find ethical or acceptable."
It took 277 attempts to produce Dolly, said Wilmut, and some of the failures resulted in defective lambs that died quickly after birth.
"It would be quite inhumane to contemplate using these techniques at this stage," he said.
Though he agreed with Harkin that "it is not possible nor even desirable to attempt to regulate the way that science progresses," Wilmut said legislators should address "the question of the individuals who will be involved, the children who would be involved."
Harkin, in a short speech that dropped the entire Senate hearing room into attentive silence, said governments should not try to slow the march of science, even for a technology as ethically troubling as human cloning.
He said it was wrong for President Clinton to issue an order to stop all federally funded human embryo research and for Sen. Christopher Bond, (R-Mo.), to propose legislation to make the research ban permanent.
He compared these government efforts to the 17th century punishment of the astronomer Galileo, who advanced Copernicus' theory that the Earth orbits the sun, instead of the other way around.
"I think to attempt to limit human knowledge is demeaning to human nature," said Harkin. "What nonsense. What utter, utter nonsense to think that somehow we are going to hold up our hands and say stop."
Several senators and two witnesses applauded Clinton's order to ban human cloning research for 90 days while the whole issue is considered by the National Bioethics Advisory Commission.
"There are aspects to life that should be off limits to science," said Bond. "We must draw a clear line. Humans are not God and they should not be allowed to play God. It is morally repugnant."
Dr. Harold Varmus, director of the National Institutes of Health, said science is not technically ready to even attempt human cloning research, even if it were permitted. He said there are technical answers about the process that can only be answered with animal research.
Varmus, however, urged that legislation on cloning be carefully drawn so that beneficial genetic research would not be affected. He said research into cloning could teach science how to control genes and manipulate them to combat disease and illness.
Wilmut said researchers at his lab are manipulating genes in sheep now and that within two years "there will be animals that produce in their milk, proteins that can treat human disease."
He said cloning technology could be used to develop treatments for hemophilia and cystic fibrosis and to help control the protein thought to cause "mad cow disease" and its human analog, Cruetzfeldt-Jakob disease.
Such technology, Wilmut said, may help science learn how to cause some human cells to regress developmentally to a point where the DNA could be easily changed to correct a genetic flaw. Such cells then could be returned to a patient to treat specific illnesses, such as blood disorders.
It may be possible, Varmus said, to use cloning technology to learn how certain genes could be "turned on" and caused to make useful tissue. That could lead to growing of bone marrow in a lab to treat a cancer patient.
Harkin challenged Varmus and Wilmut to tell of any human cloning research they knew of. Both scientists said they knew of no such research.
"It is unlikely," said Varmus, but "it is possible."