“99银河”胚胎基因编辑值得肯定

The first successful “gene editing” of human embryos to prevent transmission of inherited disease, announced this week, is a landmark in biotechnology. Humanity has gained the power to engineer its own evolution by making genetic changes that will be passed down through future generations.首例为了避免遗传疾病传播而对人类胚胎展开“基因编辑”的顺利实验在本周宣告，这是生物技术领域的一块里程碑。人类取得了设计自身演化的力量——通过将不会传授给子孙后代的基因转变。Most scientists have rightly greeted the achievement, by a US-based team working with colleagues in South Korea and China, as an experimental tour de force. Using new technology called Crispr, the researchers removed a genetic mutation that causes sudden heart failure from dozens of early human embryos with impressive precision and efficiency — and without the “off-target” impact on other genes that many feared would be an unwanted side-effect of gene editing. But much more work will be needed to assess the technique’s safety before anyone plans to implant an edited embryo into a womb.多数科学家正确地青睐由一个美国团队在与韩国和中国同事合作下获得的这项成就，视其为一个实验杰作。研究人员利用基因编辑技术CRISPR，以令人印象深刻印象的精确度和效率，从几十个早期阶段人类胚胎中手术了将不会造成突发性心脏中风的基因突变，而且没对其他基因导致“脱靶”受损，而很多人曾多次担忧这种受损将是基因编辑的一种不是非的副作用。

但是，在任何人计划将编辑好的胚胎植入子宫之前，还必须展开大量工作，以评估这种基因编辑技术的安全性。The project’s success should inspire governments, regulatory authorities and medical academies around the world to prepare more actively for clinical trials leading to genetically engineered babies. On top of thorough safety testing, extensive regulatory and ethical work with maximum public involvement will be needed before this can happen — building on the activities of bodies, such as the Nuffield Council on Bioethics in the UK and American Society of Human Genetics, that are already engaging with the subject.这个项目的顺利应当激励世界各国政府、监管机构和医学院校更加大力地打算最后将不会带给“基因工程婴儿”的临床试验。在临床试验可以启动之前，除了森严的安全性测试以外，还必须普遍的监管和伦理研究，并且让公众最大限度地参予辩论——以早已在研究这个主题的机构，如英国纳菲尔德生物伦理学理事会(Nuffield Council on Bioethics)和美国人类遗传学不会(American Society of Human Genetics)的工作为基础。

If we dismiss the idea of an absolute religious or philosophical prohibition of any tampering with human evolution, even to prevent the most horrible diseases, then there are several other issues to consider.如果我们拒绝接受以宗教或哲学为本的意味著禁令对人类演化不作任何伪造（哪怕为了防治最可怕的疾病也无法值得注意）的观念，那么还有其他几个议题必须考虑到。The “slippery slope” argument — that technology developed for good medical reasons will inevitably be applied for ethically more dubious purposes such as producing “designer babies” with enhanced looks, athletic ability or intelligence — justifies strong regulatory controls to prevent such abuse, but is surely no reason to abandon research that aims to reduce human suffering.“滑坡”论点——出于较好医学理由而研发的技术，将不可避免地被应用于在伦理上更加怀疑的目的，例如生产具备强化外表、运动能力或智力的“设计师宝宝”——解释必须强有力的监管掌控来避免这种欺诈，但这认同不是退出目的增加人类痛苦的研究的理由。In fact there are sound scientific reasons why it would be extremely hard to apply the technology to genetic enhancement. One is that the desired traits depend on many genes acting together, most of them unknown; these will lie far beyond the scope of DNA editing for the foreseeable future. Another is that the experiment published this week worked well because each embryo carrying a defective heart gene also had a healthy copy, which acted as a template for the DNA repair process. This should make Crispr editing possible in thousands of other inherited disorders in which sufferers have one good and one bad copy of the gene responsible. There would be no comparable template for genetic enhancement.事实上，有充份的科学理由解释，为什么将这项技术应用于基因强化是极为艰难的。

其中一个原因是，想的特性各不相同许多基因的联合起到，其中大多数是不得而知的；在可意识到的未来，这些将相比之下远超过DNA编辑的范畴。另一个原因是，本周公开发表的实验之所以展开成功，是因为每一个装载有缺陷心脏基因的胚胎都有一个身体健康的“副本”，后者可作为DNA修复过程的模板。这种方法应当使CRISPR编辑需要被应用于数千种其他遗传疾病——只要患者有一个好版本的基因，也有一个要负责管理的怕版本基因。

对于基因强化，就没这种可较为的模板了。Critics also question the need for gene editing when pre-implantation diagnosis (PGD), which selects healthy IVF embryos by a DNA test, can do the job, too. This is often true, but sometimes no healthy embryos are available — and, even when they are, gene editing could increase the number available to implant in the womb.当胚胎植入前遗传学临床(PGD)——通过DNA测试来自由选择身体健康的体外受精(IVF)胚胎——也可以超过某种程度目的时，批评者还批评基因编辑的必要性。这个命题往往是准确的，但有时没身体健康的胚胎能用——再说即使不存在身体健康的胚胎，基因编辑也可以减少可植入子宫内的胚胎数量。

A more practical barrier to embryonic gene editing may be cost and complexity. The Crispr procedure is bound to be expensive, even after streamlining for clinical use, and PGD will still be needed before implantation to ensure that the DNA has been repaired. The number of beneficiaries may be small in the early years, but the technology’s long-term promise is so great that society must develop a framework for its clinical development. Producing healthy babies is a laudable aim.胚胎基因编辑的更加实际障碍有可能是成本和复杂性。CRISPR手术认同是便宜的，即使在经过精简用作临床之后也不会如此，同时在植入胚胎前依然必须PGD临床，以保证DNA已被修缮。受益者的数量在初期有可能很少，但这种技术的长年前景是如此之大，社会必需为其临床研发制订一个框架。

生产身体健康的宝宝是有一点推崇的目标。

本文来源：99银河-www.pianolac.com