Cloning 3 Essay Research Paper Following surprising

Cloning 3 Essay, Research Paper

Following surprising claims this week by South Korean researchers that

they cloned an embryo from the cell of a 30-year-old woman, scientists and

ethicists said cloning of humans, while controversial, is likely to be

achieved sometime soon.

“The question isn’t whether they did it or not, but whether there is any

scientific reason to believe any top human fertility expert can’t try and even

succeed in cloning a human,” said Randall Prather, an animal embryo

researcher at the University of Missouri.

Dr. Prather and other scientists engaged in animal cloning experiments said

that breakthroughs in recent months in cloning mice and cattle, following the

cloning of a sheep in early 1997, suggest that duplicating such efforts in

humans is, if not possible now, likely to be possible soon. “The science is

there, or nearly there,” said Dr. Prather who is attempting to clone pigs. He

noted that, if anything, humans, for technical reasons, “may turn out to

actually be easier to clone than some other animal species.”

The Korean cloning announcement by fertility doctors Wednesday in Seoul

triggered a world-wide response of skepticism and alarm. Most countries,

including the U.S., have called for a moratorium on human cloning research

until many ethical and scientific issues are addressed. Indeed, the Korean

researchers said they stopped their experiment after the embryo had

developed into only four cells, meaning that it is still unknown whether the

cloned embryo could have developed into a viable or full-term and healthy


“Even in the animal research we know there is a giant leap from creating a

four-cell embryo to creating a live birth,” said Jorge Piedrahita, an

embryologist working on cloning pigs and cows at the college of veterinary

medicine at Texas A&M University. Dr. Piedrahita said in the successful

cloning of mice and cows reported in recent months “many of the cloned

embryos didn’t advance to birth, probably because they were defective in

some way.”

Still, the Korean announcement is being widely seen as evidence that

cloning is moving forward much faster than many expected. In February

1997, Ian Wilmut of the Roslin Institute in Scotland stunned the scientific

community when he reported the successful cloning of a lamb he named

Dolly from the cell of an adult sheep.

Previously, scientists had believed that it wasn’t possible to create a genetic

replica of an adult mammal by using genetic material from a cell of an adult.

That is because, unlike embryo cells that serve as the basis for all later

cells, adult cells have very specific functions that keep their activity

restricted. For example, scientists believed muscle cells could only make

other muscle cells and nerve cells could only make other nerve cells.

But Dr. Wilmut destroyed that belief. This past summer, scientists in Hawaii

using a somewhat different technique than was used in Scotland produced

numerous clones from the cells of adult mice, and two weeks ago Japanese

reserachers produced four calves from a single cow.

In a news conference in Seoul, Lee Bo Yeon, a fertility specialist at

Kyunghee University Hospital, said he and his colleague, Kim Sung Bo,

used a technique similar to the one used by the Hawaiian scientists. In the

experiment, he said he took the genetic material from the nucleus of a cell

taken from tissue near the ovum of an infertile woman and substituted it for

the genetic material in an egg removed from the same woman. As in the

Hawaiian research, the scientists prompted the egg to use the adult genetic

material to divide into a four-cell embryo.

Dr. Lee said the embryo was then destroyed because of ethical concerns.

South Korea restricts human cloning research but doesn’t yet forbid it. In the

U.S., an ethics commission in 1997 recommended a five-year moratorium on

human cloning research and President Clinton has banned the use of federal

funds to conduct human cloning experiments.

The Korean announcement led biology experts in the U.S. to question the

veracity and ethics of the Korean team. “My first response is that science by

press conference in an area as controversial as this is somewhere between

despicable and devious,” said Arthur Caplan, who runs the Center for

Bioethics at the University of Pennsylvania. Dr. Caplan said there is no way

to verify the Koreans’ claim and it raises all sorts of worries that others will

be conducting similar experiments in the absence of proof that it is safe or

even desirable.

“Human cloning claims in the past have been fraught with fraud and

misinformation,” Dr. Caplan said. “This isn’t how scientists with integrity


But several well-respected ethicists grappling with concerns since the

cloning of Dolly say that human cloning per se is not necessarily unethical

or immoral. “If in fact people want to produce a child that is their biological

duplicate there is no reason not to let it occur,” said Lee Silver, a geneticist

at Princeton University.

Dr. Silver said it may someday be widely acceptable for infertile couples or

single infertile women to use cloning as a way to conceive a child

biologically related to them. Norman Fost, a bioethicist at University of

Wisconsin, said it may even be acceptable to conceive and raise a child

who is a genetic copy in order to use the child as a bone marrow donor.

“Right now a lot of the concern about human cloning is based on the fact that

people say it makes them feel queasy,” Dr. Fost said. “These so-called

queasinartists don’t provide any proof that cloning will create children who

are in some way defective or dangerous to society.”

Ruth Macklin, an ethicist at Albert Einstein College of Medicine in New

York, said the principal concern right now is whether human cloning can be

done safely. “There is no evidence, and the Koreans don’t seem to provide

any yet either, that you can conceive a child this way without a high risk that

the child will be born physically damaged,” she said. She and others said

that, in fact, the current moratorium on research may inhibit efforts to assure

that human cloning is done safely. Most ethicists said, however, they expect

that much more work must be done in animals, especially primates, before

any human cloning should proceed.


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