科学家利用克隆技术将人体皮肤细胞转化为胚胎干细胞。这一实验可能再次引发有关克隆人的争论。研究人员的成果距创造出克隆人还很遥远,但他们首次表明,创造出同人类基因完全相同的克隆胚胎干细胞是可能的。这些胚胎干细胞就来自人类。
Scientists have used cloning technology to
transform human skin cells into embryonic stem cells, an experiment that may
revive the
controversy over human cloning.
这些干细胞可以分化成心脏、神经、肌肉、骨骼和其它所有组成人体的组织型。
The researchers stopped well short of creating a human clone. But they showed, for the first time, that it is possible to create cloned embryonic stem cells that are genetically
identical to the person from whom they are derived.
自1996年克隆绵羊多莉(Dolly)诞生以来,研究人员已经克隆出大约20个不同物种,包括兔子、山羊、奶牛和猫。然而研究人员至今无法创造出在生物性上完全相同的猴子或灵长类动物(包括人类)的克隆体,原因可能在于这些生物的生殖生物学更复杂。
These stem cells can go on to differentiate into heart, nerve, muscle, bone and all the other
tissue types that make up a human body.
但密歇根州立大学(Michigan State University)克隆专家奇贝利(Jose Cibelli)说,上述最新实验所描述的种种改进表明,研究人员创造出一只克隆猴只是时间问题。奇贝利没有参与这项实验。他还说,这同时意味着这些研究人员距离有人愿意尝试克隆人只有一步之遥,虽然克隆人还是一个遥远且令人不安的前景。
Since the birth of Dolly the sheep in 1996, researchers have cloned about 20 different species, including rabbits, goats, cows and cats. Yet they so far have been
unable to create biologically
identical copies of any
monkey or primate, including humans, possibly because their reproductive
biology is more complicated.
实验过程周三发布在专业期刊《细胞》(Cell)杂志的网站上。这项研究由俄勒冈健康与科学大学(Oregon Health and Science University)资助,法国勒迪克基金会(Leducq Foundation)提供赠款。
But the refinements described in the latest experiment suggest that 'it's a matter of time before they produce a cloned monkey,' said Jose Cibelli, a cloning
expert at Michigan State University, who wasn't involved in the study. It also means, he added, 'that they are one step closer to where the
efficiency is high enough that someone is
willing to try' to clone a person, though that remains a distant