经济学人下载:生殖技术 代孕妈妈

Reproductive technology
生殖技术

Mum, Dad and Mitomum
妈妈，爸爸与代孕妈妈

Britain may allow babies with three biological parents
英有望允许新生儿有三个亲身父母

ASSISTED reproduction is one of those rare areas in which Britain really does do world-leading research. Louise Brown, the world's first “test-tube” baby, was born in an Oldham hospital in 1978. In-vitro fertilisation, the technique that resulted in her conception, was pioneered by Robert Edwards and Patrick Steptoe, two British doctors. In 2010 Mr Edwards was awarded the Nobel prize in medicine for his work.
英国在辅助生殖技术这个十分小众的研究领域中的确达到了世界领先水平，1978年作为世界首例“试管婴儿”的路易斯·布朗就出生于英国奥尔德姆医院。体外受精胚胎移植，也是其受孕成功的关键技术，是由两位英国医生罗伯特·爱德华和帕特里克·斯特普托率先开创的。2010年爱德华博士还因此被授予了诺贝尔医学奖。

Now the government is pondering another first. On June 3rd the Human Fertilisation and Embryology Authority, which regulates assisted reproduction, opined that, as far as it could see, there was no evidence to suggest that a genetic-engineering technique called “mitochondrial transfer” was unsafe.
如今政府正考虑开创另一个第一。6月3日负责监管辅助繁殖技术的人类受精与胚胎管理局指出，就目前看来，并没有证据显示一种称作“线粒体转移”的基因工程技术是不安全的。

The technology, which was pioneered in Britain and America, is designed to cure the roughly one baby in 6,500 that would otherwise be born with a serious, untreatable mitochondrial illness. But it has caused a stir, for two reasons. Children born via the technique would have three genetic parents. And, if approved, it would be the first time that any country has allowed a genetically engineered change that could be passed on to the offspring of the person on whom it was performed.
由英国和美国率先提出的这项技术是被用来治疗那些可能一出生就患有某种严重的、无法医治的线粒体疾病的宝宝，而这种情况在6500个宝宝中大约会发生一例。但是，该技术的提出却引起了轰动，造成轰动的原因有两个。首先，通过该技术出生的孩子将会有三个遗传上的父母。其次，如果这项技术被批准，这将是首例有国家认可的技术，即基因因转基因工程发生改变的人，可以把转基因后的特征遗传给后代。

Mitochondria are tiny structures, present in almost every cell in the body, that convert food and oxygen into energy. They are the descendants of ancient bacteria which gave up their free-living lifestyle to form a symbiotic relationship with other cells. As such, they have their own tiny genomes, independent from the DNA in the cell's nucleus. Unlike that nuclear DNA, which is inherited from a child's father and mother, every mitochondrion in a person's body is descended from those inside his mother's egg.
线粒体是微型结构，几乎存在于身体中的每一个细胞中，能够将食物和氧气转化为能量。他们是远古细菌的后代，远古细菌放弃了他们独立生存的方式职位与其他细胞形成一种共生的关系。因此，他们有自己的微型基因组，独立于细胞核中的DNA。不同于核DNA是遗传自父母亲的，人类身体中的每一个线粒体出身于其母亲卵子中的线粒体。

The idea is to give a baby with misfiring mitochondria a fresh set donated by another woman. That involves removing the nucleus of the fertilised egg and transplanting it into a second, donor, egg which contains properly-functioning mitochondria.
该理论就是给缺少有效线粒体的婴儿换上由另一位女士捐献的一套充满活力的线粒体基因组。其过程包括将受精卵核移除，并将其移植至第二个包含了正常运作线粒体的捐献者的卵子上。

The resulting child would inherit roughly 20,000 genes-worth of nuclear DNA from its mother and father, and exactly 37 mitochondrial genes from the egg donor. In other words, it would inherit its genetic information from three people. And because those same donated mitochondria would find their way into a female child's eggs, the procedure would alter the DNA of her children in turn.
最终诞生的孩子将遗传到来自其父母的约2000个有遗传价值的核DNA，并且还将遗传到来自卵子捐献者的刚好37个线粒体基因。换句话说，它将从三人中遗传其基因信息。再次，因为同一位捐献者的线粒体基因组会自己找到进入女婴卵子的方法，所以这一过程也将依次改变她的孩子的DNA信息。

Three-parent babies and gene-line modifications might be expected to invite shrill headlines about “playing God”. By and large, that has not happened. Britain does not go in for American-style culture wars. But part of the credit also belongs to its cautious bureaucrats. The HFEA has a reputation for thoroughness . This report on safety is the third it has issued. Even then, it recommended a few more experiments be carried out.
拥有三个父母的宝宝以及对基因链的修改的报导可能会荣登报纸头条，同时被冠上“扮演了上帝”的尖锐标题。总的来说，这一切是不会发生的，英国并不会陷入美式的文化战争。但是，还有一部分原因是因为有关部门的谨慎行事，人类受精与胚胎管理局素以办事的彻底性闻名。这已经是第三次做出关于其安全性的报告了，即使那样，人类受精与胚胎管理局还是再推荐了几个需要实施的实验。

But thoroughness is a good thing with an experimental treatment like mitochondrial transfer, reckons Douglass Turnbull, a neurologist at the University of Newcastle and one of the pioneers of the technique. He points to the HFEA's public consultations. Most people the outfit spoke to “didn't even know what a mitochondrion was, at first,” he says. “But when the technique was explained to them, most decided that the benefits outweighed the risks.” And he points out that many other rich countries, lacking a specialist regulator of their own, look to the HFEA's work to inform their own laws.
但是对像线粒体转移这样的实验处理来说，办事彻底并不是一件好事，纽卡斯尔大学的神经病学家同样也是该技术的开创者特恩布尔·道格拉斯这样认为。他指出人类受精与胚胎管理局（HFEA）在公众咨询方面存在的问题，大多是机构人员“起初甚至完全不知道线粒体是什么，”他说道。“但是当有人向其解释了这项技术后，大多数人都认为它的好处超过了它存在的风险，”并且他还指出许多其他富有的国家，因为缺少自己的专业监管机构，正向人类受精与胚胎管理局寻求制定相关法律的帮助。

The technique has both public approval and the HFEA's blessing in principle. The government has made it a priority, too: in February it published draft regulations that, if passed by Parliament, would make Britain the first country to license mitochondrial transfer in humans. Assuming no serious problems turn up at the last minute, the first three-parent babies could arrive within a couple of years.
这项技术既获得了公众支持，原则上也获得了人类受精与胚胎管理局的同意。政府也将其列为优先事项：2月份就公布了相关法律草案，如果一旦被议会通过，这将使得英国成为首个许可人类线粒体转移的国家。假设到最后一刻都没有严重问题出现的话，预计几年后我们就能看到拥有三个父母的宝宝了。