 | Dr. Severino Antinori |
Will 2003 be the year of the first human clone? An Italian fertility expert says a patient will give birth to a cloned baby early next year but experts, including one who helped create Dolly the sheep, are skeptical. Dr. Severino Antinori told a news conference in Rome on Tuesday that the cloned baby is due in January. The maverick doctor gained fame nearly a decade ago when he helped a 62-year-old women give birth following fertility treatment with a donated egg, but he has revealed few details about his latest project. All he would say was that the cloned fetus was healthy and weighed roughly 6 pounds. Other experts in the field have grave doubts. Cloning experts doubt Antinori or his unknown colleagues have the expertise to clone a human. Although sheep, mice and pigs have been cloned, scientists have not yet produced a carbon copy of any primate. Antinori did not produce any evidence so scientists do not know if he has achieved anything or if he is just seeking publicity. Dolly the sheep was cloned using a technique called nuclear transfer. The nucleus of an egg cell was removed and replaced with the nucleus from a cell of the animal to be cloned. It is a skilled and risky technique. Only a small percentage of clones result in pregnancies and there is a high percentage of miscarriages and deformities. Even animal clones that look healthy may have genetic abnormalities or be predisposed to a decreased life span because the cells used in the cloning process acquire DNA damage as they age. Antinori has not given any clues about how the human embryo was cloned nor who the progenitor, the person who has been cloned, is. "We will wait and we will see what the DNA studies show if a baby is born," one of the experts said. "I just hope it will not have abnormalities." (Agencies) | 人类第一个克隆人会在2003年诞生吗?意大利一位人类生育学专家日前宣布,他的一位实验对象将于明年年初生下第一个克隆人。然而,许多科学家,甚至包括克隆羊"多莉"之父在内,都对此表示怀疑。 11月26日,塞韦里诺·安蒂诺里在罗马召开新闻发布会,宣布第一个克隆人将于明年1月份诞生。 十年前,这位特立独行的科学家就已经名扬天下了,当年他用一枚别人捐助的卵子使一位62岁的妇女受孕并顺利生产。但他拒绝为这次的克隆人项目透露更多的细节。只是说,这个克隆胚胎现在状态很好,非常健康,目 前体重大约是6磅。 对此,同在这一领域的其他专家纷纷表示怀疑。 克隆专家们对安蒂诺里及他那些不知名助手们在克隆人类方面的专业知识深表怀疑。尽管人们已经成功地克隆出了绵羊、老鼠和猪,但科学家们至今还没有成功地对灵长类生物进行过克隆。 安蒂诺里没有透露任何证据支持自己的言论,因此其他科学家们不知道他是真的在克隆技术上有所突破还是仅仅在哗众取宠而已。 克隆羊"多莉"的问世是应用了一项称为细胞核转移的技术。就是将卵细胞的细胞核去除,然后用预备克隆的动物的细胞核取而代之。 这是一种技术含量很高风险也极大的方法。能够让实验对象怀孕的几率非常小,而且怀孕后流产和畸形胎儿的几率也相当高。 即使看起来很健康的克隆生物也会携带畸形病变的基因,而且他们的寿命通常会比正常生物的要短,因为克隆过程中的细胞随着年龄的增长,DNA会逐渐遭到破坏。 安蒂诺里并没有描述他在克隆人过程中的胚胎转移技术,也没有提及被克隆者的身份。一位同一领域的专家说:"如果孩子真的生下来,究竟DNA会呈什么状态,我们将拭目以待。只希望不会出现畸形或变异。" (中国日报网站译) |