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The Fatal Promise of Cloning
Advocates say they will never create human fetuses.Can we believe them ?
As the cloning debate rages in the U .S ., there is news from the scientific frontier.It involves cows, but tomorrow it could easily involve humans .
Scientists at Advanced Cell Technology in Worcester, Massachusetts, tooka skin cell from Cow A, cloned it (by injecting the nucleus into a cow egg whose nucleus had been removed) , then implanted the embryo in the uterus of Cow B .
That embryo clone grew into a fetus, which, had it born, would have been Cow C.But it was not born.The fetus was removed from the uterus and harvested for its tissues.These tissues from the clone were then put back into the original Cow A .Lo and behold, it worked.These cells from the clone were not rejected by Cow A and even organized themselves into functioning tissue .
An amazing success.This is precisely what the advocates of research cloning are promising.Clone, grow it and then use the cloned tissue to create near identical replacement parts for the original animal and thus presumably put us on the road to curing such human scourges as Alzheimer s disease,Parkinson s, spinal-cord injuries and the like .
Do this in humans, and we might have thousands cured, millions relieved of suffering.Who could possible stand in the way of this research ?
We do, say cloning advocates.We would never countenance such work in humans, they say.Cows, yes, but we would never implant a cloned human embryo in the uterus of a woman and grow it to the stage of a fetus.We solemnly promise to grow human clones only to the blastocyst stage, a tiny 8-day-old cell mass no larger than the period at the end of this sentence, so that we can extract stem cells and cure diseases that way .Nothing more.No fetuses .
No implantation.No brave new world of fetal farming .
This is all very nice.But curing with stem cells is extremely complicated .
First , you have to tease out the stem cells from the blastocyst.Then you have to keep the stem cells alive, growing one generation after another while retaining their pluripotentiality (their ability to develop into all different kinds of cells) .
Then you have to take those stem cells and chemically tweak them in complex ways to make them grow into specialized tissue cells - say, neurons for a spinal-cord injury.Then you inject the neurons into the patient and get your cure .
The Advanced Cell Technology cow experiment suggests the obvious short circuit that circumvents this entire Rube Goldberg process : let the cloned embryo grow into a fetus.Nature will then create within the fetus the needed neurons, kidney cells, liver cells, etc ., in far more usable, more perfect and more easily available form .
Tempting ?No way, the cloning advocates assure us.We will never break that moral barrier.It is one thing to grow a cloned embryo, a tiny mass of cells not yet implanted.It is another thing to grow a cloned human fetus, with recognizable human features and carried in the womb of a woman .
I am skeptical of these assurances.Why?Because just a year or two ago,research advocates were assuring us that they only wanted to do stem-cell research on discarded embryos from fertility clinics but would not create a human embryo in the laboratory just for the purpose of taking it apart for its stem cells .
Well, that was then.Today these very same advocates are campaigning hard to permit research cloning - that is, the creation of human embryos for the purpose of taking them apart for their stem cells.They justify this reversal of position by invoking the suffering of millions.And they heap scorn on opponents for letting old promises and arbitrary moral barriers stand in the way of human betterment .
Well, the cow experiment shows the way to even more human betterment .
Fetal tissue offers a far simpler and more promising way to produce replacement tissues - it skips all the complications of stem-cell biology and gives you tissue that you can implant right into the human patient.Millions are suffering, are they not ?
Millions are suffering.This is precisely the argument that research-cloning advocates are deploying today to allow them to break the moral barrier of creating, for the first time, human embryos solely for their exploitation.What is to prevent“million are suffering”from allowing them to break the next barrier tomorrow, growing cloned embryos into fetuses ?
We will never go there, the research-cloning advocates assure us.Promise .
Cross my heart and hope to die.But what are such promises worth?At some point , we need to muster the courage to say no.At some point, we need to say:
We too care about human suffering, but we also care about what this research is doing to our humanity .
We need to say that today, before it is too late.The time to stop human cloning is now .
Ⅰ.Background Information
1.Cloning is the process of making a genetically identical organism through nonsexual means .It has been used for many years to produce plants (even growing a plant from a cutting is a type of cloning).Animal cloning has been the subject of scientific experiments for years, but caused little attention until the birth of the first cloned mammal in 1997, a sheep named Dolly.Since Dolly, several scientists have cloned other animals, including cows and mice.The recent success in cloning animals has sparked fierce debates among scientists, politicians and the general public about the use and morality of cloning plants, animals and possibly humans .This special report uses background stories and opinion pieces to review the latest developments in cloning research and to present the breadth of legal and ethical arguments .
2.Arguments For Human Cloning: Human cloning research would enable doctors to determine the cause of spontaneous abortions, give oncologists an understanding of the rapid cell growth of cancer , allow the use of stem cells to regenerate nerve tissues, and advance work on aging, genetics, and medicines .
3.Advanced Cell Technology: a company which studies cell .
4.Worcester : a city located in Massachusetts .
Ⅱ.Words and Expressions
advocate n .& v.辩护,拥护。
fetus (foetus) n.(已发育的)胎儿,胚胎。
embryo n.胚胎。