经济学人下载:基因编辑(1)

As far as experts are concerned, the technology of gene editing is nowhere near ready to be used to create gene-edited babies.
就专家而言，基因编辑技术还远不足以被用于创造基因编辑婴儿。

This, of course, is separate from the question of whether it is morally right to do so.
当然，这要和道德正确性的问题区分开来。

Nevertheless, around the world, would-be baby tinkerers have failed to get the memo.
但在世界各地，想成为婴儿工匠的人并没有获得谅解备忘录。

This week a Russian scientist announced his ambition to repeat a Chinese scientist's gene-editing experiment on human embryos,
本周，一名俄罗斯科学家宣布了他重复中国科学家基因编辑人类胚胎实验的雄心，

which lead to the birth of two babies with modified ccr5 genes last year.
去年在该中国科学家的实验中，两名携带修改ccr5基因的婴儿出生。

The Chinese effort was roundly condemned on grounds of safety and ethics.
出于安全和道德因素，这名中国科学家的努力遭到谴责。

Moreover, at the start of June evidence emerged that the genetic mutation in the gene CCR5,
而且在六月初，有证据表明CCR5基因中的基因突变

one that offers protection against infection from HIV, is also associated with slightly earlier death.
一种预防HIV感染的基因，也和早逝有些关联。

The finding highlights the need to understand far more about how alterations in a cell's DNA translate into changes in how it functions.
这一发现强调，我们有必要进一步了解细胞DNA 的变化如何转化为细胞功能中的变化。

There are also a variety of concerns about the basic technology
人们对于这项基本技术也有各种各样的担忧

that need to be dealt with before it can be used widely in treatments for the sick—let alone to tinker with healthy embryonic humans.
在广泛应用于治疗病人之前，需要解决这些担忧—更不用说对健康的胚胎人类进行修补了。

CRISPR-Cas genome-editing systems, often just known as CRISPR,
CRISPR-Cas基因编辑系统，也常被称为CRISPR

are molecular machines that can be programmed to home in on specific sections of DNA in the genome
是分子机器，可以通过编辑锁定基因组中的特殊DNA部分，

and cut both strands of the double helix molecule. This system allows genes to be knocked out or, in some cases, added.
并切断双螺旋分子的两条链。这一系统能让基因被敲除或在一些情况下被添加。

It is not a perfect mechanism. One concern, for example,
它并不是一个完美的机制。例如，担忧之一是

is that editing can alter DNA in places it isn't supposed to and that these "off-target" effects could trigger cancers.
编辑可以改变本应不该被更改的DNA并且这些“偏离目标”的效果可以引发癌症。

A second worry is that the cell can fill gaps with random DNA when it is making repairs.
第二个担忧是，当细胞进行修复时，它可以用随机DNA填补缺口。

These could silence genes that the organism may need.
这可能会抑制生物体可能需要的基因。

A third concern is that although CRISPR successfully hunts down and cuts out faulty DNA,
第三个担忧是，虽然CRISPR成功找到并切除了错误的DNA，

it is harder to get it to insert the right new genes.
但要让它嵌入正确的新基因更难。

Firms involved in developing CRISPR editing for use in medicines have downplayed concerns.
参与开发药用CRISPR编辑的公司并没有重视这些担忧。

Perhaps that was inevitable as they depend on investors' optimism.
或许这是不可避免的，因为他们依赖于投资者的乐观。

Rapid advances in many areas have supported the optimists' case that the gremlins in the new techniques can be overcome in time.
很多领域的迅速发展为这些乐观者提供了支持—新技术中的捣蛋鬼迟早会被克服。

"Yesterday's problems are not necessarily tomorrow's," observes Helen O'Neill, a molecular geneticist at University College London.
“昨天的问题不一定会是明天的问题，”伦敦大学学院分子遗传学家Helen O'Neill观察道。

In that vein come two papers describing a way to improve CRISPR.
基于这种思路，两篇论文描述了一种改进CRISPR的方法。

The first from a team led by Feng Zhang of the Broad Institute in Cambridge, Massachusetts, was published on June 6th, in Science.
第一篇是由马萨诸塞州坎布里奇博德研究所的张峰所领导的团队于6月6日发表于《科学》杂志上的。

The second comes this week in Nature from Samuel Sternberg's team at Columbia University in New York.
第二篇是本周由纽约哥伦比亚大学 Samuel Sternberg的团队发表于《自然》杂志上的。