Human Cloning - Saskatchewan Elocution and Debate Association

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If Not Today, Tomorrow Page 1 of 4 New Scientist, January 11, 2003 Title: If not today, tomorrow. (Special Report Human Cloning). Authors: Claire Ainsworth, Anil Anansthaswamy, Philip Cohen, David Concar, Duncan Graham-Rowe, Michael Le Page, and Ian Sample Source: New Scientist, v177 i2377 p8(4) Date: Jan 11, 2003 If the first human clone has not been born yet, it soon will be. all that's needed is a lot of cash and a little practice, new scientist's investigations suggest. and while the risks to the child are great there is little prospect of a worldwide ban. EVE was born by Caesarean section on 26 December at an undisclosed location. Her "parents" are American and belong to the Raelian cult. And that is all we know with any certainty. According to Clonaid, a company set up by the Raelians, Eve is the world's first human clone, created from a skin cell taken from her "mother". More astonishingly, Clonaid claims she is not the only one. On 3 January it says, a second clone was born, to a Dutch lesbian couple. And, Clonaid claims, three more are due to be born soon. At the press conference in Florida to announce the birth of Eve, Brigitte Boisselier, who heads Clonaid, said that Michael Guillen — a trained physicist and former science editor for the US TV channel ABC — would oversee independent tests to confirm that Eve and the other babies really are clones. But so far there is no sign of this happening. Eve's "parents" have apparently been having second thoughts about testing. A case about to be heard in Florida, calling for Eve to be placed under court protection, is not likely to help persuade them. Guillen has now suspended the testing process, saying his team of scientists has not been given access and admitting that it could all be "an elaborate hoax" to get publicity for the Raelians. His own reputation has also come under fire, especially after it emerged that he tried to sell exclusive rights to the cloning story last year. An answer may be some time in coming. But whatever the truth, Clonaid is not alone. The controversial Italian fertility doctor Severino Antinori has claimed that a cloned baby will be born in January. His erstwhile colleague Panayiotis Zavos last month announced plans to clone babies for seven infertile couples. And there may be other would-be cloners out there who are keeping their plans to themselves. HOW DIFFICULT IS CLONING? So is it really feasible that renegade scientists could clone a human? The answer has to be yes. Unlike making nuclear weapons, cloning requires no large-scale infrastructure. What is needed is a small team of scientists willing to try it despite the serious risks to both the child and the mother; a million dollars or more; and, above all, lots of human eggs. This last requirement could give an offbeat religious sect with plenty of eager volunteers a big advantage. Last year Boisselier claimed Clonaid had collected over 300 human eggs for its experiments and had lined up 50 women to carry cloned embryos. If true, such numbers would give practised cloners a good chance of success. Some animal cloners achieve up to three live births for every hundred eggs. The techniques are not overly difficult to master. Although methods vary from lab to lab and species to species, cloning usually involves removing the genetic material from an unfertilised egg and replacing it with that of an adult cell. Scientists then fool the egg into thinking it has been fertilised, usually with an electric pulse. The key tool is a micromanipulator, found in most IVF labs. This allows a skilled technician to grab an egg cell under a microscope, suck out its nucleus with a fine needle and then inject an adult nucleus using another needle. An alternative is to fuse the empty egg with a whole adult cell. Eggs are easily damaged, and manipulating them is tricky work requiring patience and a delicate touch. Even so, a few months of practice on cows' eggs taken from ovaries bought from a slaughterhouse is usually all it takes to get the hang of it, says Jose Cibelli of Michigan State University. Cibelli and his former colleagues at the Massachusetts-based cloning company Advanced Cell Technology are the only scientists to date to have attempted to clone
If Not Today, Tomorrow Page 2 of 4 New Scientist, January 11, 2003 human embryos and publish the findings. Their aim was to obtain human stem cells. The results were not good: in 19 attempts only three embryos started dividing, and the growth stopped soon. But Cibelli puts this down to a lack of human eggs. "Success in cloning is a numbers game," he says. "With cows we have hundreds of eggs. In humans, that's a luxury you don't have." ACT had to pay its egg donors $4000 each. Last year, Chinese scientists claimed to have done much better, getting dozens of cloned embryos to grow well past the stage at which they are normally implanted during IVF. But these claims have yet to be confirmed. What's more, not every mammal cloning programme has succeeded. The millions of dollars spent on dog cloning have so far failed to produce a single cloned puppy, and extensive efforts to clone rhesus monkeys have not led to a single successful pregnancy. However, many experts believe that these efforts have failed because these species' reproductive systems are unusually difficult to manipulate, rather than because of any fundamental barrier. For instance, when scientists created ANDi, the first genetically modified monkey, their main difficulty was keeping the monkey embryos alive in culture beyond the four-cell stage. During IVF, human embryos are routinely grown past this stage. All this suggests that, in theory at least, maverick scientists could indeed clone a baby. But has Clonaid really done it? According to Cibelli, the main reason to be suspicious is that it claims to have produced not just one cloned baby, but two, with another three on the way and just five miscarriages. To have five clones born live from just 10 attempts would represent an astonishing success rate — especially since in Cibelli's experience human eggs are more fragile than cows' eggs. He is also surprised that Clonaid claims to have achieved all this by cloning skin cells. In his experience, the cumulus cells that surround developing eggs are better donors. Yet animal work has shown that cloning is something of an art. Success can be unpredictable and inexplicable. IS CLONING SAFE? If little Eve really is a clone, she could suffer a host of serious health problems. Some might not show up until she is in her sixties — if she survives that long. Although scientists still do not understand exactly why, cloning is very risky for both the offspring and the mother. In every species that has been cloned, the vast majority of cloned embryos die before birth. And even the clones that survive to birth often have debilitating or fatal problems. "There is absolutely no reason to expect the situation to be different in humans," states a letter put out by cloning experts Randall Prather and Gerald Schatten, and the creator of Dolly the sheep, Ian Wilmut. "Until there is compelling evidence that the situation is different in human embryos, it is grossly irresponsible to attempt to clone children." Cloning involves transferring the genetic material of an adult cell such as a skin cell — reportedly used to create Eve - to an empty egg. But a skin cell is "programmed" to be skin. That is, the genes needed for skin are turned on and the rest are turned off. For a cloned embryo to develop normally, the skin genes need to be turned off and embryonic genes turned on. Putting an adult nucleus into an egg does somehow reprogram it, but this process is far from perfect. And the physical transfer of the nucleus can also damage the delicate egg. The result is that some embryos never divide, while others don't grow enough to be implanted into the uterus of a surrogate mother. Those that appear healthy enough to implant often spontaneously abort or are stillborn. Only a few per cent survive to birth. The fetus isn't the only one at risk. Cloned animals and their placentas can be unusually large. That poses a serious threat to the life of the surrogate mother. A 1999 study of 12 cows pregnant with cloned embryos found that a third died from complications. The few cloned animals born alive often suffer from a surprisingly wide array of deformities. These include: lung and heart problems; huge tongues; flattened faces; bad kidneys; blocked intestines; weak immune systems; twisted feet and gross obesity a few weeks after birth. The defects are sometimes so severe the animals have to be put down. In humans, they would require lifelong treatment.
Page 1 and 2: SASKATCHEWAN ELOCUTION AND DEBATE A
Page 3 and 4: Brave New World Page 1 of 5 Smithso
Page 5 and 6: Brave New World Page 3 of 5 Smithso
Page 7: Brave New World Page 5 of 5 Smithso
Page 11 and 12: If Not Today, Tomorrow Page 4 of 4
Page 13 and 14: Man and superman Page 2 of 3 The Ec
Page 15 and 16: Seeing Double: The Cloning Conundru
Page 23 and 24: Send in the clones Page 1 of 1 Cana
Page 25 and 26: The Threat of Biotech Page 2 of 3 C
Page 27 and 28: This embryonic cloning is worth pur
Page 29 and 30: Ban cloning. Do you copy? Page 2 of
Page 31: Ban cloning, not its life-saving co

Human Cloning - Saskatchewan Elocution and Debate Association

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