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S Unit 8: Science and technology Reading–writing: Chinese scientists have successfully cloned monkeys (B2) a) Read an article from a news magazine on a recent scientific experiment which could have far-reaching consequences. 1 For the past decade, Mu-Ming Poo, the director of the Institute of Neuroscience in Shanghai, has been on a quest to clone monkeys that can be used to study human disease. Recently, researchers in his institute announced a major milestone: the births of the first two monkey clones created using the same technique as behind Dolly, the sheep. After Dolly’s birth in 1996, scientists quickly figured out how to clone mice, pigs, dogs, cats, cows and more. But primates long proved elusive. After various unsuccessful attempts it was suggested that primate cloning – and by extension human cloning – is impossible using this method. In an interview with The Atlantic , Professor Mu-Ming Poo said that human cloning is absolutely not his intention. That, he added, requires its own ethical debate. But he wants to use cloning to expand the number of genetically modified monkeys for further research. With cloning, it is possible to genetically modify monkey cells in a dish, grow the cells in large numbers, and then create clones from them. The last step requires taking DNA out of the genetically modified cells and putting it into an egg – a procedure called somatic-cell nuclear transfer. The two monkeys were created this way, as was Dolly, the sheep. The cloning efficiency is still low – though comparable to that in other animals. To create the two monkeys, the team transferred DNA into 127 eggs. Of those, 109 developed into embryos, and 79 were transferred into 21 surrogate monkey mothers. There were six pregnancies and just two live births. Given these numbers, cloning genetically modified monkeys will remain very expensive. Cloned and genetically modified monkeys, says Christopher Navara, a biologist at the University of Texas at San Antonio, could be very useful for studies of some diseases, but less so for others. Childhood disease could be studied in young monkeys immediately. Aging-related diseases like Alzheimer’s or Parkinson’s would take decades, though. Crab-eating macaques, the species to which the two monkeys belong, live to 25 to 30 years. It’s also unknown whether cloning creates other health problems. While concerns about Dolly’s premature aging may have been overblown, clones can be abnormal at birth. And no one knows what health issues may be specific to primates. That’s why Anthony Perry of the University of Bath is cautious about using clones of genetically modified primates to study human disease. “You wouldn’t use this approach with all these unknowns,” he says. “If you want to make a genetic model of disease, the last thing you want is use a model you don’t know much about.” This experiment may soon tell us how cloning affects primates. They are just two for now, but the Institute of Neuroscience expects more clones to be born in the coming months. (Sarah Zhang, The Atlantic, 24 January, 2018; adapted) 5 10 15 20 25 30 35 40 45 50 55 b) Read the text again and find the original phrases and sentences that have been rephrased below. Copy them into your exercise book and add the line numbers. 1. The publication of new findings … . 2. After having tried in vain to do this, … . 3. Cloning is still very difficult and often not successful. 4. Gaining results with respect to certain diseases can be a long process. 5. The consequences of using genetically modified primates for research are still highly uncertain. c) Having read the article above, you have decided to write to the news magazine expressing your views on this issue . In your e-mail you should: describe the experiment explain the difficulties discuss possible consequences Write around 250 words . 138 Semester self-checks Nur zu Prüfzwecken – Eigentum des Verlags öbv