Human Cloning - Saskatchewan Elocution and Debate Association

More documents

Recommendations

Info

If Not Today, Tomorrow Page 3 of 4 New Scientist, January 11, 2003 Cloning companies claim most cow clones that do survive are perfectly healthy. They point out that "large offspring syndrome" also occurs in cattle created by IVF, so the problem may be poor culture conditions rather than cloning itself. And pig cloners report far fewer birth defects, suggesting some species are easier to clone than others. However, other scientists say it is too early to declare any clone normal. It is just six years since the birth of Dolly, the first cloned mammal, and few clones other than mice have yet lived out their natural lifespan. Dolly herself prematurely developed arthritis. What little we know suggests clones might die earlier than normal. A year ago, Japanese researchers reported that 83 per cent of their cloned mice died after two years — over three times the rate for mice created by IVF or normal breeding. And some tests on cows suggest that clones are even less bright than the average bovine. Would-be human cloners have always pledged to screen out defective embryos to eliminate problems encountered with animal clones. Boisselier told New Scientist that Clonaid had looked at gene expression in the cloned human embryos it created and found no problems, but she would not reveal any details. Most experts say comprehensive tests of this kind can't be done, because the genetic defects in clones are believed to be too subtle and too widespread to screen for with existing technology. Researchers recently showed that there are dramatic abnormalities in the level of activity of hundreds of genes in the placentas of cloned mice. They also detected a similar but lower level of genetic chaos in the livers of newborn mice clones. Measuring and predicting the effects of these abnormalities in every tissue of a developing fetus is impossible. HOW CAN WE TELL IT A CLONE REALLY IS A CLONE? Verifying whether a baby is a clone or not is straightforward with modern DNA fingerprinting technology. But with all the secrecy surrounding maverick cloners, satisfying sceptical scientists will not be easy. "Extraordinary claims have to be supported by extraordinary evidence," says the inventor of DNA fingerprinting, Alec Jeffreys of the University of Leicester. "That means bringing into force the full weight of forensic DNA typing systems, including all the safeguards and procedures that exist in that technology." DNA fingerprinting looks at highly variable regions of our genome, in which short sequences are repeated many times. The number of times a particular sequence is repeated varies from person to person, and on each of the two copies of each chromosome. The chances of two people having the same pattern is extremely small. A normal child's DNA fingerprint would be a combination of those of its parents. But a cloned baby would have just one "parent", and their DNA fingerprints should be exactly the same. Of course, mutations can occur in any cell in the body, so it is possible that the clone's profile would differ very slightly from the "parent", requiring further testing. However, it is not enough for self-proclaimed cloners to provide matching samples. They have to prove that one sample is from the child and the other from the person cloned. Given the controversy surrounding such claims, it is crucial that the entire process is foolproof. "What you need is some trustworthy person to take the samples," says Rudolf Jaenisch, a cloning expert at the Whitehead Institute in Boston. Jeffreys goes further. He insists that the sampling and testing should be done independently by not just one, but two labs. "Ideally, the entire procedure should be videotaped all the way through to ensure that there's no possibility of sample substitution." Even then, Jeffreys suspects that more testing will be called for. "The scepticism in the scientific community will be so intense that there will be some suspicion that very clever substitution has occurred," he says. But there is a way to check. A little of the DNA in cells is found outside the nucleus, in organelles called mitochondria. The mitochondria in a clone come from the donor of the egg, rather than from the person cloned. So as long as Eve's mother didn't provide the donor egg as well as the skin cell that was cloned, a mitochondrial DNA test could help settle any argument over the source of the samples. CAN WE STOP WOULD-BE CLONERS? "We must prevent human cloning by stopping it before it starts,"
If Not Today, Tomorrow Page 4 of 4 New Scientist, January 11, 2003 announced President Bush last April. Yet if Clonaid is to be believed, the first human clone was already growing in her mother's womb as these words were uttered. Despite the almost universal condemnation of the renegade cloners such as Clonaid, preventing human cloning will not be easy. Since Dolly the cloned sheep was born six years ago, the prospect of human cloning has prompted over 40 countries to ban it (see Map). There has also been an attempt by the UN to piece together an international treaty banning human cloning. But even if such a treaty gets off the ground, it will only be effective in the states that sign up to it, says Frederick Kirgis, an expert in international law at the Washington and Lee University in Virginia. Each country would have to amend its domestic law to bring the treaty's provisions into force, which could take many years. And there is always the possibility that non-signatory states will allow human cloning to go ahead. UN treaties can often be breached with impunity, says Kirgis. "Some treaties have enforcement mechanisms written into them," he says. "But most of them don't." Despite broad support for a ban, not to mention the new sense of urgency brought on by the announcement of Eve, there is still a complete lack of consensus on how it should be carried out, says Arthur Caplan, a bioethicist at the University of Pennsylvania in Philadelphia and an adviser to the UN committee dealing with cloning. The best we could hope for at present is a moratorium, he says. The problem is that while some countries want a blanket ban on all forms of human cloning, others such as Britain believe any ban should exclude therapeutic cloning — creating cloned embryos to obtain embryonic stem cells for treating diseases. To get round this, some countries have suggested that the UN should ban reproductive cloning now and worry about therapeutic cloning later. But Spain and other states oppose this because they see no legal or moral distinction between therapeutic and reproductive cloning. Nowhere is the division on this issue greater than in the US. George Bush has lent his support to a bill that would make human cloners liable to up to 10 years in prison and a $100,000 fine. A second bill introduced by Republican senator Arlene Spector would ban only reproductive cloning. Perhaps the way forward would be to copy South Korea's approach, where last week officials raided Clonaid's local subsidiary. Korean law does not ban cloning, but officials are considering bringing charges on the grounds of unsafe medical practice. RELATED ARTICLE: CLONING IS THE EASY PART... For Clonaid, cloning humans is just the start. The next step, the Raelians say, is to use clones to make people immortal. All you have to do — once you have "speed-grown" a cloned cell into an adult — is to wipe their memory, erase their personality and then replace both of them with the memories and personality from the wannabe immortal. It sounds ludicrous, and it is. For starters, any clone, just like any twin, would be a unique individual. "Wiping" a clone's memory would be tantamount to murder — if it were possible. "Given our current state of knowledge, it seems unthinkable something like this could be achievable," says Michael Rugg of the Institute of Cognitive Science in London. "Memories aren't stored in the brain like books in a library." Scientists think that memories are held in the brain by modifying the strengths of connections between huge numbers of neurons. But there is little else they agree on. Just how memories are encoded remains a mystery, and it may vary for different kinds of memory. What's more, the brain has tens of billions of neurons, each linked to thousands of others. That makes the idea of reading memories a staggeringly complex proposition. Miguel Nicolelis at Duke University in Durham, North Carolina, is at the forefront of research into "reading" information from brains. His group has used the signals from a monkey's brain to control a robot arm. But he says even the intention to transfer one person's mind into another's brain is preposterous. "The idea is simply absurd," he says. "It has no scientific basis or merit."
Page 1 and 2: SASKATCHEWAN ELOCUTION AND DEBATE A
Page 3 and 4: Brave New World Page 1 of 5 Smithso
Page 9: If Not Today, Tomorrow Page 2 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

Create successful ePaper yourself

Delete template?

Save as template?