美国试管婴儿 将可选择"最聪明的"胚胎？

如果有一天，你可以选择生育一个小“爱因斯坦”，也可以生育一个智商普通的孩子，你会做出什么样的选择？据科学家预计，未来10年内，人类将可以使用试管婴儿技术选择“最聪明”的胚胎。

Genetics research， conceptual artwork。CHINA DAILY

　　Couples undergoing IVF treatment could be given the option to pick the “smartest” embryo within the next 10 years， a leading US scientist has predicted。

　　据美国一名权威科学家预计，未来10年之内，做试管婴儿的夫妇将能够选择“最聪明”的胚胎。

　　IVF：in vitro fertilization 体外受精联合胚胎移植技术，又称“试管婴儿”

　　Stephen Hsu， senior vice president for research at Michigan State University， said scientific advances mean it will soon be feasible to reliably rank embryos according to potential IQ， posing profound ethical questions for society about whether or not the technology should be adopted。

　　美国密歇根州立大学主管科研的副校长徐道辉（斯蒂芬·徐）说，科学进步意味着人类不久就能够对胚胎的潜在智商给出可靠的评分，这项技术是否应该使用将是一个深刻的社会伦理问题。

　　Hsu’s company， Genomic Prediction， already offers a test aimed at screening out embryos with abnormally low IQ to couples being treated at fertility clinics in the US。

　　徐道辉的基因组预测公司已经为在美国不孕不育诊所接受治疗的夫妇提供了一项检测服务，旨在筛查出智商异常低的胚胎。

　　“Accurate IQ predictors will be possible， if not the next five years， the next 10 years certainly，” Hsu told the Guardian。“I predict certain countries will adopt them。”

　　徐道辉对《卫报》记者说：“准确的智商预测是可能的，即使不是未来5年内，那么在未来10年内也肯定可以。我预计一些国家会采纳这项技术。”

　　The prospect of a new generation of genetically selected babies has prompted concerns about unintended medical consequences and the potential for deepening existing social inequalities。The science underpinning the claim that intelligence can be meaningfully predicted by genetic tests is also contentious。

　　新一代基因选择婴儿的前景引发了人们对于意外医疗后果和现有社会不平等可能加剧的担忧。基因检测能够有效预测智商的科学技术也引发了争议。

Peter Donnelly， a professor of statistical science at the University of Oxford， said any such IQ predictions should be treated with “huge caution”， adding：“I have grave misgivings about it on ethical grounds。I think it’s a really bad idea。”

　　牛津大学统计学教授彼得·唐纳利说，应该“十分谨慎”地对待此类智商预测。他说：“出于伦理原因，我对此非常担忧。我认为这是一个非常糟糕的想法。”

　　Since the 1990s， couples undergoing IVF have been able to screen their embryos for mutations in single genes that cause serious diseases such as cystic fibrosis， as well as conditions like Down’s syndrome， caused by chromosome abnormalities。

　　自上世纪90年代以来，接受试管受精的夫妇已经能够对他们的胚胎进行筛选，以发现单个基因的突变，这些突变会导致严重的疾病，比如囊性纤维化，以及染色体异常导致的唐氏综合征等。

　　Many other traits， including height， physical appearance， intelligence and disease susceptibility， are known to be partly heritable。But because the genetic component is spread thinly over hundreds or even thousands of DNA regions， it has previously been impossible to screen for these traits。

　　许多其他特征，包括身高、外貌、智力和疾病易感性，都被认为是部分遗传的。但由于遗传组分稀疏地分散在数百甚至数千个DNA区域，以前不可能对这些特征进行筛选。

　　In the past decade， as vast genetic databases have been established， this picture has changed。Through analyzing many genes， each making a tiny contribution， it has been possible to calculate what are called polygenic risk scores， which give a person’s likelihood of getting a particular disease or having a certain trait。

　　在过去的十年里，随着大量基因数据库的建立，这种情况已经发生了改变。通过分析大量基因，每个基因都做出了微小的贡献，就有可能计算出所谓的多基因风险评分，即一个人患某种特定疾病或具有某种特征的可能性。

　　Genomic Prediction is the first company to take embryo screening into this grey area of risk forecasting， offering to alert couples if an embryo has an “outlier” score for risk of cancers， diabetes， heart disease， dwarfism or low IQ。

　　基因组预测公司是第一家将胚胎筛查纳入风险预测这一灰色地带的公司。如果胚胎在癌症、糖尿病、心脏病、侏儒症或智商低下等风险方面的评分“异常”，它就会提醒做筛查的夫妇。

　　Medical staff put clothes on the newborn test-tube baby at a hospital in Xi‘an， Northwest China’s Shaanxi province。[Photo/Xinhua]

　　Prediction for IQ is not good enough to give a reliable ranking， but Hsu said that knowing an embryo has a low score could still be desirable。

　　智商预测目前还不足以给出可靠的评分，但徐道辉表示，如果一个胚胎的智商评分较低，人们可能还是很想知道。

　　“Maybe the bottom 1% embryo will grow up to be a great person … even be a scientist， but the odds are against it，” he said。“I honestly feel if we can calculate that score and find a real negative outlier there’s an ethical responsibility for us to report that。”

　　徐道辉说：“也许评分最低的1%的胚胎长大后会成为一个优秀的人……甚至成为一名科学家，但这种可能性很小。我真的觉得，如果我们能计算出这个评分，发现它低得十分异常，那么我们就有道德责任予以告知。”

　　The company projects that once high-quality genetic and academic achievement data from a million individuals becomes available， expected to be within five to 10 years， it will be able to predict IQ to within about 10 points。

　　该公司预计，在5至10年内，一旦100万人的高质量基因和学术成就数据可用，它将能够预测智商，误差在10分以内。

　　Hsu is reticent about whether screening for high intelligence would be ethically justified， saying：“Let me just decline to answer that at the moment。”

　　徐道辉不愿评论高智商筛查是否符合伦理标准，说“目前我拒绝回答这个问题”。

　　In some countries， such as Singapore， there is likely to be a high level of public acceptance and demand for such tests， he suggested。“I think the overwhelming majority would say yes， absolutely， parents should be allowed to do that，” he said。“Before you write your piece， you might just want to think that a billion people on the other side of the world might have a different view。”

　　徐道辉说，在一些国家，比如新加坡，公众对此类检测的接受度和需求可能会很高。他说：“我认为绝大多数人肯定会赞成允许父母这样做。在你写这篇报道之前，也许应该想想地球另外一端的10亿人可能有不同的看法。”

　　Whether such tests will become available in the UK would depend on approval from the Human Fertilization and Embryology Authority （HFEA）。

　　这种检测方法能否在英国实施将取决于英国人工授精与胚胎学管理局的批准。

　　“If the HFEA decides that it’s not right for the UK， I will respect that，” Hsu said， but predicted that “rich people from the UK will fly to Singapore” if they are unable to get the tests locally。

　　他说：“如果英国人工授精与胚胎学管理局认为这对英国不合适，我会尊重这个决定。”但他预测，如果英国富人无法在当地进行这项检测，“他们会飞到新加坡去做的。”

　　Some in the UK take the view that prospective parents have a right to access such tests。“I don’t think people should be deprived of that knowledge，” said Prof Simon Fishel， the founder of Care Fertility。

　　在英国，一些人认为未来的父母有权进行此类检测。生育关怀组织的创始人西蒙•费舍尔教授说：“我认为不应该剥夺人们的这种知情权。”

　　Fishel questioned whether there is any ethical difference between picking an embryo ranked highest for IQ or sending a child to a private school。“What’s wrong with ranking an embryo if you can rank a child？” he said。“I think there are plenty of people who’d choose embryo Oxford [rather] than embryo A-level failure。”

　　费舍尔质疑挑选智商最高的胚胎和送孩子去私立学校之间是否存在伦理上的差异。“如果你能给孩子评分，那给胚胎评分又有什么错呢？”他说。“我认为有很多人会选择未来能考取牛津的胚胎而不是无法通过英国中学高级水平考试的胚胎。”

　　In practice， though， couples often have only a few embryos to choose from。And there are concerns about unintended consequences。For instance， there is some evidence linking higher polygenic scores for academic ability to higher likelihood of autism。

　　但实际上，夫妇们通常只有几个胚胎可供选择。此外，人们还担心会出现意想不到的后果。例如，有证据表明，学术能力的多基因得分越高，患自闭症的可能性就越大。

　　The technology is controversial， but that does not mean it will not gain acceptance in the future， Hsu said， drawing parallels with the reaction to IVF in its early days。

　　徐道辉说，这项技术存在争议，但这并不意味着它在未来不会被接受，这与早期人们对体外受精的反应类似。

　　“The IVF pioneers … were called monsters， Frankenstein doctors；it was predicted that these babies would have health problems，” he said。“I am actually reassured by that。IVF is completely normalized now。Everyone who is pointing their finger at [Genomic Prediction] now should go back and read those articles。”

　　他说：“试管婴儿的先驱被称为怪物，弗兰肯斯坦医生。当时人们预测这些婴儿会有健康问题。实际上，我对此很放心。试管受精现在已经完全正常化。现在，所有指责（基因组预测）的人都应该回去读读那些文章。”