单选题 Scientists have discovered a way of manipulating a gene that turns animals into drones incapable of becoming bored even when performing repetitive tasks. Experiments on rhesus monkeys have shown for the first time that animal behaviour can be permanently altered, turning the subjects from aggressive to "compliant" creatures. The genes are identical in humans. Although the research is intended to advance the treatment of mental illness, it will raise images of the Epsilon caste created by Aldous Huxley to carry out menial jobs in his novel, Brave New World. It could also do away with the need for motivational coaching and perhaps one day provide a cure for those who dread returning to work on Mondays.
The experiments—detailed in the journal Nature Neuroscience —involved blocking the effect of a gene in the brain called D2, which cut the link between the monkeys" motivation and perceived reward. Instead of speeding up with the approach of a deadline or the prospect of a "treat", the monkeys could still work enthusiastically for long periods. "Most people are motivated to work hard and well only by the expectation of reward, whether it"s a pay cheque or a word of praise," said Barry Richmond, a neuro-biologist at America"s National Institute of Mental Health, who led the project. "We could remove that link and create a situation where repetitive hard work would continue without any reward. "
The experiments involved getting monkeys to operate levers in response to colour changes on screens in front of them. Normally they work hardest and fastest with the fewest mistakes if they think a reward for the "work" is imminent. But Richmond"s team found they could make the monkeys work their hardest and fastest all the time, without any complaint or sign of slacking, just by manipulating D2 so that they forgot about expectation of reward. "We make decisions all the time based on how valuable we think a reward is and how much time we think it is going to take to get it," said Richmond. "In depression, people think no reward is worthwhile and all work is too burdensome. In obsessive compulsive disorder, people work and are never satisfied by what they have done. If we can find the disturbance in the brain circuitry related to emotions and reward, we might be able to relieve the symptoms."
He said the technicalities of permanently altering human behaviour by gene manipulation are currently too complex and humans who underwent this treatment to become live manifestations of Huxley"s Epsilons would not function well. "They would be indiscriminate and not be able to appreciate that their efforts were wasted if there was a problem further along a production line," Richmond said. "It would be more to the point for us to motivate people using normal motivating factors. " However, he and other scientists acknowledge that methods of manipulating human physical and psychological traits are just around the corner and the technology will emerge first as a lucrative add-on available from IVF clinics. "There"s no doubt we will be able to influence behaviour," said Julian Savulescu, a professor of ethics at Oxford University. He said: "Genetically manipulating people to become slaves is not in their interests, but other changes might be. We have to make choices about what makes a good life for an individual."
Richmond"s findings were discussed at a Royal Society meeting organised by Bob Edwards, the scientist whose work led to the creation of Louise Brown, the world"s first test tube baby. In a presentation entitled Designing Babies: What the Future Holds, Yuri Verlinsky, a scientist from the University of Chicago who is at the forefront of embryo manipulation, said: "As infertility customers are investing so much time, money and effort into having a baby, shouldn"t they have a healthy one and what is to stop them picking a baby for its physical and psychological traits?" The advent of the technology is considered so serious in America that a meeting to discuss setting up a legal framework for "germline" genetic manipulation is being held in Washington, D.C. in December.

单选题 It can be concluded from the passage that the Epsilon caste created by Aldous Huxley in his novel Brave New World are ______.

单选题 The original purpose of the research introduced in the passage was ______.

单选题 Which of the following CANNOT be true about the gene D2 according to the passage?

单选题 According to neuro-biologist Barry Richmond, the methods of manipulating human physical and psychological traits ______.

单选题 It can be concluded from the passage that the scientist Yuri Verlinsky ______ the technology of gene manipulation.