Biologists in Japan have cloned 581 mice from one original donor mouse, Livescience reported. The scientists made the mice over 25 generations of cloning; that is, from making clones from clones from clones, 25 times over.
根據(jù)Livescience的報道，日本生物學家用一只小鼠的基因供體克隆出581只小鼠。這些科學家們克隆了25代小鼠，即：用克隆鼠克隆新的小鼠，一共克隆了25次。

They could probably make animal clones indefinitely, the research team wrote in a paper published last week in the journal Cell Stem Cell.
研究團隊在上周發(fā)表在《干細胞》期刊中的論文稱，他們很有可能會讓動物無休無止地克隆下去。

Really. Check out the last sentence of their abstract: "Our results show that repeated iterative recloning is possible and suggest that, with adequately efficient techniques, it may be possible to reclone animals indefinitely."
是這樣嗎？我們來看看論文摘要的最后一句話：“我們的研究結(jié)果證明多代克隆是可能實現(xiàn)的。如果技術(shù)到位，那么克隆出無窮多代的動物都是可能的?！?/div>

The 581 cloned mice were made using an improved version of somatic cell nuclear transfer, the technique that created Dolly the cloned sheep in 1996.
這581只小鼠是用改進后的體細胞克隆技術(shù)克隆得到的，這一技術(shù)最早是在1996年克隆多莉時發(fā)明的。

Previously, researchers using somatic nuclear cell transfer would get fewer and fewer animals every time they tried to make a clone from a clone. Eventually, they wouldn't get any new clones at all. Cloned mammals also often died sooner than their non-cloned counterparts.
在此之前，運用體細胞克隆技術(shù)反復克隆動物時，被克隆的動物數(shù)量會越來越少，直到最終無法克隆出新動物為止。被克隆出的哺乳動物也會比非克隆的同類動物死得更早。

The cloning team protected the mice's DNA from the genetic abnormalities they (the humans) think reduced the efficiency of previous cloning efforts. The researchers didn't lose any cloning efficiency over their 25 generations, they reported, and their cloned mice lived normal lifespans of about two years.
這支研究團隊保護了小鼠的基因，使其不發(fā)生基因異常。他們認為，基因異常正是降低克隆形成率的罪魁禍首。研究者稱，這25代小鼠的克隆過程中克隆形成率并沒有降低，小鼠的壽命也很正常，約能生存兩年時間。

Cloning could help reproduce animals for farming or conservation, Sayaka Wakayama, a biologist at the RIKEN Center for Developmental Biology who led the cloning study, said in a statement.
日本理化研究所的生物學家若山清香是這次研究的負責人，他在一個聲明中提到，克隆技術(shù)可以繁殖動物，為農(nóng)業(yè)和動物保護服務。

This isn't the first time Wakayama has made some big strides in cloning. He previously cloned mice from bodies of mice that had been frozen for 16 years.
這已經(jīng)不是若山清香在克隆技術(shù)上的第一個重大成就了。此前他曾經(jīng)以一只冰凍了16年的小鼠為供體克隆出了一只小鼠。