Sperm were artificially created in a breakthrough experiment which raises ethical questions. Here a sperm approaches an egg(dailymail.co.uk) |
Scientists have used artificial sperm to restore fertility in a breakthrough that could allow thousands of men to fulfill their dream of fatherhood. In ‘hugely exciting’ experiments, they have made sperm from scratch, and, for the first time, succeeded in using it to produce healthy young. Remarkably, the baby mice in the experiments went on to have offspring themselves. The landmark research paves the way for new drugs for infertility, the heartbreaking but little-understood condition that affects one in six couples. But it also opens a Pandora’s box of ethical dilemmas. Possibilities raised range from men being made ‘redundant’ from the process of creating life, to babies being created through entirely artificial means. Critics also question whether it is right to meddle with the building blocks of life just to allow couples to satisfy their desire to have children. Scientists have been trying for years to coax embryonic stem cells – ‘master cells’ widely seen as a repair kit for the body – into turning into sperm. They have had some success but any mice that became pregnant by such means gave birth to unhealthy offspring that quickly died. Now, Japanese scientists have come up with a series of steps that appear to solve the problem. They started with stem cells taken from mouse embryos in the first days of life and, using a cocktail of chemicals and vitamins, turned them into sperm in the earliest stages of development. These were then transplanted into the testicles of infertile mice, where they grew into fully-functional sperm. The ‘a(chǎn)rtificial sperm’ were then used to fertilise eggs, leading to the birth of 60 ‘grossly healthy’ baby mice, who went on to have families of their own, the journal Cell reports. The Kyoto University researchers hope to be able to repeat their success using slivers of skin as starting material, allowing men to father children that are genetically their own. Josephine Quintavalle, of campaign group Comment on Reproductive Ethics, said the work was ‘total narcissism’ and raised the possibility of ‘male eggs’ from men’s skin and ‘female sperm’ from women’s skin. She added: ‘Who needs men? Who needs women? All that is required now are artificial wombs and we will have completely rewritten human reproduction.’ (Read by Lee Hannon. Lee Hannon is a journalist at the China Daily Website.) (Agencies)
|
科學(xué)家近日突破性地培育出“人工精子”,可以使不育男性重獲生育能力,幫助數(shù)千男性實(shí)現(xiàn)“父親夢”。 在激動人心的實(shí)驗(yàn)中,科學(xué)家從零開始制造精子,而且首次成功地用這些精子培育出了健康的鼠寶寶。 值得注意的是,這些老鼠寶寶還能自己繁殖后代。這項(xiàng)具有里程碑意義的研究為研發(fā)新的治療不育的藥物鋪平了道路。每六對夫婦中,就有一對遭遇到令人傷心,但原因不明的不育難題。 但該研究也開啟了潘多拉魔盒,帶來了倫理困境。這可能使男性在生寶寶的過程中成為“多余的人”,也可能使嬰兒完全成為“人造寶寶”。 批評者們質(zhì)疑,為了滿足人們?yōu)槿烁改傅脑竿?,就打亂正常的生育過程是否妥當(dāng)。 多年以來,科學(xué)家們一直試圖將胚胎干細(xì)胞培育成精子。這種主細(xì)胞被普遍看做人體的維修工具箱??茖W(xué)家們?nèi)〉眠^一些成果,但通過這種方式受孕的老鼠生出的后代無一健康,不久便夭折。 現(xiàn)在,日本科學(xué)家們已經(jīng)提出一系列措施,這一難題有望解決。 首先,他們?nèi)∠吕鲜笈咛ジ杉?xì)胞,使用化學(xué)品和維他命混合物,將干細(xì)胞培育成早期精子。然后將其植入不育老鼠的睪丸里,它們便會發(fā)育為功能健全的精子。 據(jù)《細(xì)胞》雜志報(bào)道,這些“人工精子”隨后用于使卵細(xì)胞受精,并培育出60個非常健康的老鼠寶寶,它們自己就能傳宗接代。 日本京都大學(xué)的研究者們希望可以復(fù)制他們的成功經(jīng)驗(yàn),以皮膚組織為原始材料,讓男性擁有自己的親生孩子。 英國公益組織“生殖倫理學(xué)評論”的約瑟芬?昆塔瓦萊卻說這項(xiàng)工作“太自戀了”,最后很可能從男性皮膚中提取出“男性卵子”,從女性皮膚中提取出“女性精子”。 她說:“還需要男人和女人嗎?現(xiàn)在唯一需要的就是人工子宮,我們將徹底改寫人類的生殖史。” 相關(guān)閱讀 (中國日報(bào)網(wǎng)英語點(diǎn)津 實(shí)習(xí)生沈清 編輯:Julie) |
Vocabulary: from scratch: without any previous preparation or knowledge(從頭開始;從零開始) Pandora’s box: a process that generates many complicated problems as the result of unwise interference in something(潘多拉魔盒,指邪惡之源) meddle with: 瞎弄,亂動 building block: a basic unit from which something is built up(組成部份;構(gòu)成要素) coax:哄騙,勸誘 |