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Updated: 2002-12-02 01:00

Scientists Doubt Imminent Birth of Human Clone (2002/12/02)
克隆人明年一月問世?特立獨(dú)行科學(xué)家遭質(zhì)疑 (2002/12/02)
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)

人類第一個(gè)克隆人會(huì)在2003年誕生嗎?意大利一位人類生育學(xué)專家日前宣布,他的一位實(shí)驗(yàn)對(duì)象將于明年年初生下第一個(gè)克隆人。然而,許多科學(xué)家,甚至包括克隆羊"多莉"之父在內(nèi),都對(duì)此表示懷疑。

11月26日,塞韋里諾·安蒂諾里在羅馬召開新聞發(fā)布會(huì),宣布第一個(gè)克隆人將于明年1月份誕生。

十年前,這位特立獨(dú)行的科學(xué)家就已經(jīng)名揚(yáng)天下了,當(dāng)年他用一枚別人捐助的卵子使一位62歲的婦女受孕并順利生產(chǎn)。但他拒絕為這次的克隆人項(xiàng)目透露更多的細(xì)節(jié)。只是說(shuō),這個(gè)克隆胚胎現(xiàn)在狀態(tài)很好,非常健康,目前體重大約是6磅。

對(duì)此,同在這一領(lǐng)域的其他專家紛紛表示懷疑。

克隆專家們對(duì)安蒂諾里及他那些不知名助手們?cè)诳寺∪祟惙矫娴膶I(yè)知識(shí)深表懷疑。盡管人們已經(jīng)成功地克隆出了綿羊、老鼠和豬,但科學(xué)家們至今還沒有成功地對(duì)靈長(zhǎng)類生物進(jìn)行過克隆。

安蒂諾里沒有透露任何證據(jù)支持自己的言論,因此其他科學(xué)家們不知道他是真的在克隆技術(shù)上有所突破還是僅僅在嘩眾取寵而已。

克隆羊"多莉"的問世是應(yīng)用了一項(xiàng)稱為細(xì)胞核轉(zhuǎn)移的技術(shù)。就是將卵細(xì)胞的細(xì)胞核去除,然后用預(yù)備克隆的動(dòng)物的細(xì)胞核取而代之。

這是一種技術(shù)含量很高風(fēng)險(xiǎn)也極大的方法。能夠讓實(shí)驗(yàn)對(duì)象懷孕的幾率非常小,而且懷孕后流產(chǎn)和畸形胎兒的幾率也相當(dāng)高。

即使看起來(lái)很健康的克隆生物也會(huì)攜帶畸形病變的基因,而且他們的壽命通常會(huì)比正常生物的要短,因?yàn)榭寺∵^程中的細(xì)胞隨著年齡的增長(zhǎng),DNA會(huì)逐漸遭到破壞。

安蒂諾里并沒有描述他在克隆人過程中的胚胎轉(zhuǎn)移技術(shù),也沒有提及被克隆者的身份。一位同一領(lǐng)域的專家說(shuō):"如果孩子真的生下來(lái),究竟DNA會(huì)呈什么狀態(tài),我們將拭目以待。只希望不會(huì)出現(xiàn)畸形或變異。"

(中國(guó)日?qǐng)?bào)網(wǎng)站譯)

 
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