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Download Presessional Prac Reading Test 2016 - Booklet 1
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Practice Reading Test Text A Look at this newspaper article about using science to design babies. Answer the questions in Section A of Booklet 2. If you’re looking for a designer super-baby, you can forget it Mark Henderson, The Times Online, 27 April 2007 Paragraph 1 The smiling young woman who stared out from the front page of this newspaper yesterday does not look very much like the face of eugenics, the study of improving human beings by influencing their reproduction. Yet her case has added to the controversy surrounding this area of science, with much of the heated debate between those who are and against the procedure taking place in the media. Paragraph 2 If the organisation that controls fertility treatments (techniques to help people have babies) gives permission to her doctor, the woman will soon start IVF (in vitro fertilisation) treatment, even though she can have babies naturally. Her eggs will then be checked for a gene that increases the risk of breast cancer. This gene killed her mother, her grandmother and her greatgrandmother, and she carries it herself. Now she has an opportunity to make sure that her daughters will not get the gene. Paragraph 3 For some, though, this is not a reason to celebrate. They are scared that we are coming closer and closer to the making of designer babies. According to these people, parents will soon be able to make their dreams of producing the next superstar footballer like Cristiano Ronaldo or Hollywood actress like Scarlett Johansson come true. 1 Paragraph 4 Their concern is that the checking of embryos, which uses a technique called pre-implantation genetic diagnosis (PGD), is being used for an increasing range of medical problems. It was originally licensed only for genes that cause life-threatening diseases that cannot be cured by doctors, such as cystic fibrosis. Now, it has become acceptable to use the technique when the risk of illness is just 80 per cent, and for a cancer that can be prevented. Paragraph 5 From here, the critics argue that it will soon become acceptable to test for genes that are only slightly linked to disease, or to no disease at all. For example, doctors might start checking for the recently discovered gene that raises the risk of obesity (the disease of being overweight), even though diet and exercise play more important roles. Selection of socially desirable traits such as intelligence and good looks could follow. Paragraph 6 It is easy, though, to overstate the risks. Talk of designer babies adds little to useful debate about PGD, because its possibilities are firmly limited by science. It is certainly a powerful technology that has helped hundreds of families to have a healthy child. But it is entirely unsuitable for the mass production of babies-to-order. Paragraph 7 To begin with, PGD is impossible without IVF. To examine an embryo’s genes, it is first necessary to take a cell from it. This can be done only with an embryo created in the science laboratory. The technique also requires a good supply of embryos to test: if there is something wrong with a single embryo created naturally, there would be no others to put inside the mother. Paragraph 8 This makes it impossible for many couples who might like a designer baby to try to make one. Despite all its benefits, IVF is unappealing for those who can make babies naturally. Success rates are poor, and it involves surgery. There are also side-effects for the future mother: menopausal symptoms such as hot flushes, and on rare occasions, ovarian hyperstimulation syndrome, which can lead to death. Producing babies the natural way is a more efficient option for those who can manage it, as well as being more fun. Paragraph 9 Then there is the matter of what to look for. At present, scientists only know of about 200 single genes that cause or make people more likely to have problems, for which it is quite simple to test. The kinds of characteristics that parents would want in a true designer baby, however, are not much influenced by individual genes. Paragraph 10 Intelligence, height, good looks, athletic ability – all have elements that can be passed on from parents to children, but this is determined by a complex number of genes, with relationships that are poorly understood. Each characteristic will also be affected by environment, both inside the mother and in childhood: there is no guarantee that the designer baby will do what it is designed to do. It is one thing to expect PGD to find the gene for cystic fibrosis; quite another to identify a future Oxford University student. Paragraph 11 People may eventually find a solution to get around these difficulties. Our understanding of the field is progressing all the time, and it is possible that a combination of genes that increases intelligence might eventually be discovered. And ‘gene chips’, instruments that can test for thousands of genes at once, are improving all the time. Paragraph 12 However, embryologists using PGD can work only with what nature provides. No matter how 2 many embryos are produced, each will get all its genetic material equally from its parents. You can order a designer baby with the brains of the physicist Stephen Hawking and the looks of the supermodel Kate Moss. But if mum and dad are not particularly intelligent or good-looking, nothing is going to happen. PGD is unable to make genetic ‘haves’ from the children of ‘havenots’. Paragraph 13 Improved technology could actually make matters worse for future parents of a designer baby. In the checking of genes, there is such a thing as too much information. Even when looking for a single mutation, such as the one that causes Huntington’s disease, all the embryos that are created sometimes test positive. Add in the thousands of problems that a gene chip might one day identify, and it will become almost impossible to find one that has nothing wrong with it. Do you select the embryo with ‘clever’ genes but with the possibility of developing schizophrenia? Or the athletic one likely to develop type 2 diabetes later on in life? Paragraph 14 Knowing about the natural limits to the checking of embryos is necessary to evaluate its place in medicine. To oppose the technique because of its unlikely uses ignores its proven ability to change life and health. PGD is a great tool for preventing genetic diseases that are passed down from parent to child, causing suffering to whole families. For the eugenic design of superhumans, however, it is essentially useless. Text B Look at this article about human genetic engineering. Answer the questions in Section B of Booklet 2. King, D. (2007) The Threat of Human Genetic Engineering. Human Genetics Alert. Paragraph 1 The main debate around human genetics currently centres on the ethics of genetic testing, and possibilities for genetic discrimination and selective eugenics. While ethicists and the media constantly rehash these issues again and again, a small group of scientists and publicists are working towards an even more frightening prospect: the intentional genetic engineering of human beings. Just as Ian Wilmut presented us with the first clone – a genetically identical copy – of an adult sheep, Dolly, as something which cannot be reversed, so these scientists aim to establish a new kind of eugenics, before we have ever had a chance to decide whether this is the direction we want to go in. The publicists are trying to convince us that these developments are inevitable. The Campaign Against Human Genetic Engineering (CAHGE) has been set up in response to this threat. Paragraph 2 Currently, genetic engineering is only applied to non-reproductive cells (this is known as 'gene therapy') in order to treat diseases in a single patient, rather than in all their descendants. Gene therapy is still very unsuccessful, and we are often told that the prospect of reproductive genetic engineering is remote. In fact, the basic technologies for human genetic engineering (HGE) have been available for some time, and at present are being refined and improved in a number of ways. We should not make the same mistake that was made with cloning, and assume that the issue is one for the far future. Paragraph 3 In the first instance, the likely justifications of HGE will be medical. One major step towards reproductive genetic engineering is the proposal by US gene therapy pioneer, French Anderson, to begin doing gene therapy on foetuses to treat certain genetic diseases. Although not directly targeted at reproductive cells, Anderson's proposed technique poses a relatively high risk that 3 genes will be 'inadvertently' altered in the reproductive cells of the foetus, as well as in the blood cells which he wants to fix. Thus, if he is allowed to go ahead, the descendants of the foetus will be genetically engineered in every cell of their body. Paragraph 4 Another scientist, James Grifo of New York University, is transferring cell nuclei from the eggs of older to younger women, using similar techniques to those used in cloning. He aims to overcome certain fertility problems, but the result would be babies with three genetic parents, arguably a form of HGE. In addition to the two normal parents, these babies will have mitochondria (gene-containing structures which control energy production in cells) from the younger woman. Paragraph 5 Anderson is a declared advocate of HGE for medical purposes, and was a speaker at a symposium last year at UCLA, at which proponents of HGE proudly set out its capabilities. At the symposium, which was attended by nearly 1,000 people, James Watson, the discoverer of DNA, promoted the use of HGE not merely for medical purposes, but for ‘enhancement’. Paragraph 6 In Silver’s Re-Making Eden (1998), Princeton University biologist Lee Silver celebrates the coming future of human ‘enhancement’, in which the health, appearance, personality, cognitive ability, sensory capacity and life-span of our children all become artefacts of genetic engineering, literally selected from a catalogue. Silver acknowledges that the costs of these technologies will limit their full use to only a small elite, so that over time society will segregate into what he calls the ‘GenRich’ and the ‘Naturals’. Paragraph 7 Silver imagines a future America in which the GenRich, all carrying synthetic genes that were created in the laboratory, accounts for 10 per cent of the population. All aspects of the economy, the media, the entertainment industry, and the knowledge industry are controlled by members of the GenRich class, and Naturals work as low-paid service providers or as labourers. Silver predicts that if the accumulation of genetic knowledge and advances in genetic enhancement technology continue, the GenRich class and the Natural class will become entirely separate species with no ability to cross-breed, ‘with as much romantic interest in each other as a current human would have for a chimpanzee’. Silver believes that these trends should not and cannot be stopped, because to do so would infringe on liberty. Paragraph 8 Most scientists say that what is preventing them from embarking on HGE is the risk that the process will itself generate new mutations, which will be passed on to future generations. This is the main reason why official scientific and ethical bodies forbid attempts at HGE. However, experience with genetically engineered crops shows that we are unlikely ever to arrive at a situation when we can be sure that the risks are zero. Instead, when scientists are ready to proceed, we will be told that the risks are ‘acceptable’ compared to the benefits. Meanwhile, there will be people telling us loudly that since they are taking the risks with their children, we have no right to interfere. Paragraph 9 One of the key flaws in the argument of those who support the possibility of HGE for medical purposes is that there seem to be very few good examples where it is the only solution to the medical problem of genetic disease. The main advantage of HGE is said to be the elimination of disease genes from a family. Yet in nearly all cases, existing technologies for the genetic testing of embryos allow the avoidance of actual disease. There are only a few very rare cases where HGE is the only option. As for couples who are certain to produce a genetically disabled child and cannot, or do not want to deal with this possibility, they can adopt a child or use donor eggs or sperm in IVF. The question we have to ask is whether we should develop HGE technology in order to satisfy a very small number of people. 4 Paragraph 10 The arguments for the first uses of HGE will be medical but the main market for the technology will be ‘enhancement’. Existing trends leave little doubt about what to expect. Sophisticated medical technology and medical personnel are already employed in increasingly fashionable cosmetic surgery. Another example is the use of genetically engineered human growth hormone (HGH), which is routinely prescribed in the USA to normal short children with no hormone deficiency owing to parental and market pressure. If these pressures already exist, how much stronger will they be for a technology with as great a power to manipulate human life as HGE? Paragraph 11 In essence, we are seeing a sanitised version of the old eugenics, updated for modern times. Instead of ‘elimination of the unfit’, HGE is presented as a tool to end, once and for all, the suffering associated with genetic diseases. And in place of ‘improving the race’, the current emphasis is on freedom of choice, where ‘reproductive rights’ become consumer rights to choose the characteristics of your child. However, there is still time to prevent this scenario before it becomes reality. We need an international ban on HGE and cloning and there is a good chance this can be achieved, since both are already illegal in many countries. Of course it may be impossible to prevent a scientist, somewhere, from attempting to clone or genetically engineer humans. But there is a great difference between a society which would jail such a scientist and one which would permit HGE to become widespread and respectable. If we fail to act now, we will only have ourselves to blame. 5