Cloning offers the possibility of making exact copies of ourselves. Should this be allowed? What benefits and dangers may cloning bring?

A Clone Is Born

Gina Kolata

1. On July 5, 1996, at 5:00 p.m., the most famous lamb in history entered the world. She was born in a shed, just down the road from the Roslin Institute in Roslin, Scotland, where she was created. And yet her creator, Ian Wilmut, a quiet, balding fifty-two-year-old embryologist, does not remember where he was when he heard that the lamb, named Dolly, was born. He does not even recall getting a telephone call from John Bracken, a scientist who had monitored the pregnancy of the sheep that gave birth to Dolly, saying that Dolly was alive and healthy and weighed 6.6 kilograms.

2. No one broke open champagne. No one took pictures. Only a few staff members from the institute and a local veterinarian who attended the birth were present. Yet Dolly, who looked for all the world like hundreds of other lambs that dot the rolling hills of Scotland, was soon to change the world.

3. When the time comes to write the history of our age, this quiet birth, the creation of this little lamb, will stand out. The world is a different place now that she is born.

4. Dolly is a clone. She was created not out of the union of a sperm and an egg but out of the genetic material from an udder cell of a six-year-old sheep. Wilmut fused the udder cell with an egg from another sheep, after first removing all genetic material from the egg. The udder cell's genes took up residence in the egg and directed it to grow and develop. The result was Dolly, the identical twin of the original sheep that provided the udder cells, but an identical twin born six years later.

5. Until Dolly entered the world, cloning was the stuff of science fiction. It had been raised as a possibility decades ago, then dismissed, something that serious scientists thought was simply not going to happen anytime soon. Now it is not fantasy to think that someday, perhaps decades from now, but someday, you could clone yourself and make tens, dozens, hundreds of genetically identical twins. Nor is it science fiction to think that your cells could be improved beforehand, genetically engineered to add some genes and remove others.

6. True, it was a sheep that was cloned, not a human being. But there was nothing exceptional about sheep. Even Wilmut, who made it clear that he was opposed to the very idea of cloning people, said that there was no longer any theoretical reason why humans could not clone themselves, using the same methods he had used to clone Dolly. "There is no reason in principle why you couldn't do it." But, he added, "All of us would find that offensive."

7. We live in a time when we argue about pragmatism and compromises in our quest to be morally right. But cloning forces us back to the most basic questions that have plagued humanity since the dawn of recorded time: What is good and what is evil? And how much potential for evil can we tolerate to obtain something that might be good? Cloning, with its possibilities for creating our own identical twins, brings us back to the ancient sins of vanity and pride; the sins of Narcissus, who so loved himself, and of Prometheus, who, in stealing fire, sought the powers of God. So before we can ask why we are so fascinated by cloning, we have to examine our souls and ask, What exactly so bothers many of us about trying to make an exact copy of our genetic selves? Or, if we are not bothered, why aren't we?

8. We want children who resemble us. Even couples who use donor eggs or donor sperm, search catalogs of donors to find people who resemble themselves. Several years ago, a poem by Linda Pastan, called "To a Daughter Leaving Home," was displayed on the walls of New York subways. It read:

Yet if we so love ourselves, reflected in our children, why is it so terrifying to so many of us to think of seeing our exact genetic replicas born again, identical twins years younger than we? Is it one thing for nature to form us through a genetic lottery, and another for us to take complete control, abandoning all thoughts of somehow, through the mixing of genes, having a child who is like us, but better? Normally, when a man and a woman have a child together, the child is an unpredictable mixture of the two. We recognize that, of course, in the old joke in which a beautiful but dumb woman suggests to an ugly but brilliant man that the two have a child. Just think of how wonderful the baby would be, the woman says, with my looks and your brains. Aha, says the man. But what if the child inherited my looks and your brains?

9. Cloning brings us face-to-face with what it means to be human and makes us confront both the privileges and limitations of life itself. It also forces us to question the powers of science. Is there, in fact, knowledge that we do not want? Are there paths we would rather not pursue?

10. The time is long past when we can speak of the purity of science, divorced from its consequences. If any needed reminding that the innocence of scientists was lost long ago, they need only recall the comments of J. Robert Oppenheimer, the genius who was a father of the atomic bomb and who was transformed in the process from a supremely confident man, ready to follow his scientific curiosity, to a humbled and troubled soul, wondering what science had let loose.

11. Before the bomb was made, Oppenheimer said, "When you see something that is technically sweet you go ahead and do it." After the bomb was dropped on Hiroshima and Nagasaki, in a chilling speech delivered in 1947, he said: "The physicists have known sin; and this is a knowledge which they cannot lose."

12. As with the atom bomb, cloning is complex, multi-layered in its threats and its promises. It offers the possibility of real scientific advances that can improve our lives and save them. In medicine, scientists dream of using cloning to reprogram cells so we can make our own body parts for transplantation. Suppose, for example, you needed a bone marrow transplant. Some deadly forms of leukemia can be cured completely if doctors destroy your own marrow and replace it with healthy marrow from someone else. But the marrow must be a close genetic match to your own. If not, it will lash out at you and kill you. Bone marrow is the source of the white blood cells of the immune system. If you have someone else's marrow, you'll make their white blood cells. And if those cells think you are different from them, they will attack.

13. But suppose, instead, that scientists could take one of your cells -- any cell -- and merge it with a human egg. The egg would start to divide, to develop, but it would not be permitted to divide more than a few times. Instead, technicians would bathe it in proteins that direct primitive cells, embryo1 cells, to become marrow cells. What started out to be a clone of you could grow into a batch of your marrow -- the perfect match.

14. More difficult, but not inconceivable, would be to grow solid organs, like kidneys or livers, in the same way.

15. Another possibility is to create animals whose organs are perfect genetic matches for humans. If you need a liver, a kidney, or even a heart, you might be able to get one from a specially designed pig clone.

16. The possibilities are limitless, scientists say, and so, some argue, we should stop focusing on our hypothetical fears and think about the benefits that cloning could bring.