2019年翻译资格考试英语笔译初级模拟题：基因与遗传

　　基因和行为：双重遗传生物学因素

　　或许并不能决定人的命运，但是基因对人类行为的影响显然比人们普遍认为的要大得多。很多自出生后便被分开的孪生子身上呈现出各种相似点，包括恐惧感、业余爱好、身体语言等。心理学家小托马斯.J.布恰德说，许多此类行为都是“那些打算研究行为遗传学的人根本就不会想到要去留意的”。他是明尼苏达大学孪生与收养研究中心的主任。

　　布恰德称，到目前为止，他们已经完成了详尽的心理测试和问卷调查，研究对象包括约50对被分开抚养的同卵孪生子，25对被分开抚养的异卵孪生子，以及由若干对一同长大的孪生子组成的对照组。布恰德说：“孪生子在姿态和表达风格上的相似令我们感到惊讶。这或许是该项研究最令我们着迷的特点。”孪生子往往拥有相似的癖好、姿势、说话的速度和节奏、习惯以及惯常讲的笑话。

　　许多孪生子有着相似的穿着风格。一对从未见过面的孪生兄弟来到了英国，他们蓄着相同的胡须，梳着相同的发型，带着相同的金丝边眼镜，穿着相同的衬衫。还有一对孪生子的洗漱用品几乎完全一样，包括同一个牌子的科隆香水和某种瑞典品牌的牙膏。

　　尽管许多被分开抚养的孪生子有着不同的职业和教育程度，但是调查者一再发现他们在兴趣爱好方面的相似点。有一对孪生子都是志愿消防队员，有一对都是副行政司法长官，有一对孪生兄弟在各自的地下室中有着相似的工作间，还有一对孪生姐妹的厨房布置惊人地相似。

　　在变态行为或精神病理学方面，布恰德还没有掌握足够的信息用于归纳总结，但是他已经发现了反复呈现的类似点。有一对孪生姐妹都很迷信;另一对只要受到最轻微的刺激就会落泪，经询问，她俩从小就都是这样。“她俩一同参加了一个聊天节目，在被问及其中一个问题的时候，两人同时哭了起来。”布恰德说。

　　然而，最惊人的普通精神病理学案例却来自一对被分开抚养的异卵孪生子。其中一个是由其贫穷的亲生父母养大的，另外一个被一户殷实的中上阶层家庭所收养。现在，这两个人都被认为具有反社会的个性，他们缺少控制冲动的能力，而且都有犯罪史。虽然异卵孪生子平均拥有50 010的相同基因，但是布恰德认为在这对孪生子身上相同基因的数量或许要高得多。

　　明尼苏达大学心理学家奥克·特立根进行的测试表明，对于被分开抚养的同卵孪生子来说，其个性的相似点几乎跟一同长大的同卵孪生子一样广泛。他的个性调查问卷列出了“社交亲近度”、“伤害逃避”和“幸福感”等不同的尺度。尤其令研究者感到吃惊的，是发现“传统主义”这种意味着保守和尊重权威的性格竟然也可以遗传。布恰德说，事实上，通过他和别人的研究，已经发现了有大约11种性格特征似乎深受遗传的影响。

　　总的来说，明尼苏达州的研究者的发现对那些认为环境是性格的根本塑造者的人们提出了有力的反驳。布恰德预言，教科书恐怕得重新书写了。

　　如今世界很多地方的人们都有充足的食物，生存繁殖比以往任何时候都更为容易，所以很容易以为人类已经停止了进化。但是一项颇具争议的新研究结果却不这么认为。据其分析，人类的进化速度非但不曾放缓，相反，在过去4万年里加快了速度，过去5000年更是加快了100倍。这意味着尽管有些人游走异乡，与异族人通婚，但各大洲大多数人正在变得越来越不同，他们的基因并没有越来越同质化。

　　1800个人类基因已加快了进化，占人类基因组的7%。大多数基因突变都因人口猛增而产生。人口增长时，基因突变也会增加，这就提升了产生有益的基因变体的机会，这种有益的基因变体将提升人类的生存能力，并在整个人群中传播(这和大群昆虫制造抗杀虫剂的基因的速度比小群快是同样道理)。

　　研究人员没有破译大部分进化的基因，但他们说其中很多似乎都是应对人类饮食变化，和人类农垦初期曾肆虐过的中毒疾病卷土重来的结果。有些基因突变使成人能够消化淀粉、脂肪酸和牛奶中的乳糖。还有些增强了人类抵御疟疾、爱滋病和黄热病等疾病的能力。

　　参考译文

　　Genes and Behavior: A Twin Legacy

　　Biology may not be destiny, but genes apparently have a far greater influence on human behavior than is commonly thought. Similarities ranging from phobias to hobbies to bodily gestures are being found in pairs of twins separated at birth. Many of these behaviors are "things you would never think of looking at if you were going to study the genetics of behavior," says psychologist Thomas J. Bouchard, Jr., director of the Minnesota Center for Twin and Adoption Research at the University of Minnesota.

　　Bouchard reports that so far, exhaustive psychological tests and questionnaires have been completed with approximately 50 pairs of identical twins reared apart, 25 pairs of fraternal twins reared apart and comparison groups of twins reared together. "We were amazed at the similarity in posture and expressive style," says Bouchard. "It's probably the feature of the study that's grabbed us the most." Twins tend to have similar mannerisms, gestures, speed and tempo in talking, habits, and jokes.

　　Many of the twins dressed in similar fashion - one male pair who had never previously met arrived in England sporting identical beards, haircuts, wire-rimmed glasses and shirts. One pair had practically the same items in their toilet cases, including the same brand of cologne and a Swedish brand of toothpaste.

　　Although many of the separated pairs had differing types of jobs and educational levels, the investigators are finding repeated similarities in hobbies and interests - one pair were both volunteer firefighters, one pair were deputy sheriffs, a male pair had similar workshops in their basements and a female pair had strikingly similar kitchen arrangements.

　　Bouchard doesn't have enough information on abnormal behavior or psychopathology to make generalizations, but he has found repeated similarities. One pair of women were both very superstitious; another pair would burst into tears at the drop of a hat, and questioning revealed that both had done so since childhood. "They were on a talk show together and both started crying in response to one of the questions," says Bouchard.

　　The most striking example of common psychopathology, however, came from a pair of fraternal twins reared apart. One had been reared by his own poor family; the other had been adopted into a "good solid upper - middle-class family." Both are now considered to be antisocial personalities, suffering from lack of impulse control, and both have criminal histories. Although fraternal twins share, on average, 50 percent of their genes, Bouchard suggests that the overlap is probably considerably more with this pair.

　　Personality similarities between the identical twins reared apart are almost as pervasive as they are with identical twins reared together, according to the results of a test developed by University of Minnesota psychologist Auke Tellegen. His personality questionnaire contains scales such as "social closeness", " harm avoidance" and "well-being". The researchers were especially surprised to find that "traditionalism" - a trait implying conservatism and respect for authority - can be inherited. In fact, says Bouchard, his and other studies have found about 11 personality traits that appear to have significant genetic input.

　　Overall the emerging findings of the Minnesota study constitute a powerful rebuttal to those who maintain that environmental influences are the primary shaping forces of personality. The textbooks are going to have to be rewritten, Bouchard predicts.

　　Plentiful food has made it easier than ever before to survive and reproduce in many parts of the world, so it's tempting to think that our species has stopped evolving. But a controversial new study says that isn't so .Far from slowing down, human evolution has sped up in the past 40,000 years and has become 100 times faster in the past 5,000 years alone, according to the analysis. This means that even though some people have been globe-trotters who interbreed, most humans on different continents are becoming more different, rather than blending together into one genetically homogenous race.

　　Evolution has accelerated in 1800 human genes, which encompass about 70/o of the human genome. Most of the mutations resulted from dramatic population booms. As populations expand, the number of mutations increases, boosting the chances for a beneficial genetic variant that can improve survival and sweep through a population (in the same way that a large population of insects develops a gene for resistance to a pesticide faster than a small population).

　　Although the researchers don't know the identity of most of the genes, they say quite a few appear to be responses to changes in diet and a new wave of virulent diseases that swept through human populations as they began farming. Some mutations allow adults to digest starch, fatty acids, and lactose in milk. Others improve the resistance to diseases, such as malaria, AIDS, and yellow fever.