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If it works in humans as it has in other mammals, cloning will be technically possible, but also terribly inefficient and risky.
According to experts, producing a single viable clone will require scores of volunteers to donate eggs and carry embryos, most of which will have major abnormalities and never come to term. The clones that do survive may suffer more subtle problems that would show up well after birth.
Here's how it can be done: Doctors harvest up to 15 eggs each from up to 40 donors who have been injected with fertility drugs. About 400 eggs are produced. Then cells are taken from the cloning candidate.
The nucleus of each egg is sucked out with a fine needle. The DNA-free eggs and the donor cells are placed next to one another and zapped with electricity, which causes them to fuse. Some of the rebuilt eggs divide to form embryos.
Because embryos often fail to implant, each surrogate mother gets several at once. Even so, up to 50 surrogates may be needed (not necessarily all at once) to ensure nine or 10 pregnancies. Of these, most will terminate early by miscarriage or by abortion when abnormalities are found. The single viable baby may be normal--or maybe not.
Ben-Abraham gained fame at age 17, when he entered the Guinness Book of Records as the world's youngest doctor. To both scientific and ethical critics of the process, Ben-Abraham says the time has come for the technology: Why hold it back? He says that he and his team are taking the heat for the sake of humanity. Within a couple of weeks the team will go underground, stop talking to the media, choose a location, and initiate the process.
He is part of an international team of six infertility experts including two from the United States, two Austrians, an Italian, and himself. The doctors knew of each other's prominence in the field and agreed to work together.
In picking the perfect couple for this historic procedure, 김포출장마사지 Ben-Abraham says the couple has to be medically and psychologically fit. They want people between 25 and 40, not too young, but a serious and sophisticated couple that will be able to handle the emotional impact that this procedure will bring. The procedure will only be offered to infertile couples.
The confidence of the team is wonderful, Ben-Abraham says. Each scientist on the team has specific expertise, prominence, and experience that may make it happen.
Human cloning would require the same technology that created Dolly, the sheep, by taking DNA from the single adult cell and injecting it into an egg.
Cloning is the kind of issue so confounding that you envy the purists at either end of the argument. For the Roman Catholic Church, the entire question is one of world view--whether life is a gift of love or just one more industrial product, a little more valuable than most. Those who believe that the soul enters the body at the moment of conception think it is fine for God to make clones: He does it about 4,000 times a day, when a fertilized egg splits into identical twins. But for the scientist to do mechanically what God does naturally is to interfere with his work, and no possible benefit can justify that presumption.
On the other end of the argument are the libertarians who don't like politicians, clerics, or ethics boards interfering with what they believe should be purely individual decisions. eproduction is a most fateful lottery. In their view, cloning allows you to hedge your bets. While grieving parents may be confused about the technology, cloning, even if it works, is not resurrection. Their motives are their own business.
In the messy middle are the vast majority of people, who view the prospect with a vague alarm, an uneasy sense that science is dragging us into dark woods with no paths and no easy way to turn back. Ian Wilmut, the scientist who cloned Dolly but has come out publicly against human cloning, was not trying to help sheep have genetically related children. "He was trying to help farmers produce genetically improved sheep," notes Hastings Center ethicist Erik Parens. "And surely that's how the technology will go with us too." Cloning, Parens says, "is not simply this isolated technique out there that a few deluded folks are going to avail themselves of, whether they think it is a key to immortality or a way to bring someone back from the dead. It's part of a much bigger project. Essentially the big-picture question is, to what extent do we want to go down the path of using reproductive technologies to genetically shape our children?"
At the moment, the public in the United States is plainly not ready to move quickly on cloning. In a Time/CNN poll in February, 90% of respondents reported that they thought it was a bad idea to clone human beings.
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