Spring Cloning

SO YOU COULDN'T SQUEEZE INTO the Jackie O auction, and were outbid every time the gavel slammed down at Pamela Harriman's? Take heart: the next big auction of the possessions of a glamorous female is underway. Earlier this month, animalkeepers at the Roslin Institute in Scotland sheared Dolly the sheep. Dolly, of course, is the first mammal cloned from a single adult cell (NEWSWEEK, March 10). Her creamy-white wool, says the United Kingdom Cystic Fibrosis Trust, which Roslin selected to handle the sale and reap the proceeds, has already drawn bids from around the world, including from one American whom the trust described to NEWSWEEK as ""in the public eye.'' Not in the market for a sweater? If experiments underway in labs from Utah to Australia pan out, soon there may be lovely collectibles in calfskin, pigskin and bunny fur - all from cloned animals.

It has been only three months since researchers at Roslin stunned the world with an announcement that biologists didn't think they would hear until well into the next millennium, if ever: the creation of a mammal by cloning a single cell from an adult ewe. The feat was widely thought to be impossible, prohibited by little-understood laws of developmental biology. Well, if there ever were such laws, they've been repealed. No one has yet produced Dolly Jr. But at the Bio '97 conference in Houston this month, the hallways and bars were buzzing with rumors that surrogate-mother rabbits, cows and sheep are pregnant with fetuses that trace their origins not to two parents but to one cell. The success, of course, has made scientists, ethicists and policymakers focus even more intently on the ultimate question: can, and will, humans be cloned?

Everyone in the cloning game sees dollar signs beckoning, and is keeping his tricks proprietary. In all the methods, though, a cell from an animal - from the skin of a sheep, from muscle tissue of a rabbit, from the embryo of a cow - is grown in a nutrient medium in a lab dish. A technician uses an ultrathin needle to remove the cell's nucleus, which contains the genetic instructions for producing an exact copy of the animal from which the cell came. The nucleus is injected into an ovum whose own nucleus has been removed. The result of this transplant is that the ovum is now genetically programmed to develop, just like a fertilized egg, into a complete animal after it gestates in the uterus of a surrogate mother. But in this case the animal is a genetic copy of the donor.

At Utah State University, embryologist Ken White and self-described ""gene jockey'' John Morrey have been tinkering with the key step: how cells are grown in the lab dishes. The hurdle has been to stop the cells at a very specific point in their cycle of growing and dividing. The idea is to snatch up the cell nuclei and shoot them into an ovum just at the moment that the genes are ""reprogrammable'' - when all of them can be switched on by special molecules in the ovum, so that the pregnancy results in a complete, healthy newborn (and not a clump of tissue). The scientists have taken cells from adult rabbit muscle, injected the nucleus into rabbit ova and transplanted the ova into surrogate-mother rabbits. This week they expect to learn through ultrasound whether any of the rabbits are pregnant with the clones-to-be. If any are, in about two weeks they will find out whether they have any furry little blessed events.

At PPL Therapeutics, which funded the Roslin research that produced Dolly, half a dozen or so cows roaming the firm's Blacksburg, Va., site are pregnant with fetuses created by cloning the skin cells of cow fetuses. PPL should know early next year whether the pregnancies have gone to term and produced healthy calves. And researchers at Australia's Monash University, led by Alan Trounson, have produced cloned calves. He removes one cell from a cow embryo and grows it in a lab dish until it has divided several times. Then he separates the resulting cells and makes each one grow and divide. So far he has made 500 identical embryo clones this way - apparently a world record - and, using surrogate-mother cows, has grown six of them into calves. James Robl of the University of Massachusetts at Amherst has made several pigs and cows pregnant through his cloning technique, and is optimistic enough that he's established a company to commercialize it. He hopes the pig and cow fetuses he creates will become organ and tissue donors for people.

Three years before Dolly made her debut, reproductive biologist Neal First of the University of Wisconsin created the first cattle clones from embryo cells, which are easier to clone than adult cells. After the Dolly announcement he immediately set his laboratory group to work on cloning from the skin cells of adult sheep, as well as cells from a fetal calf. First won't say whether any of his animals is pregnant, nor exactly what technique he's using. But he confirms that he is preparing to patent his methods, suggesting that they are different from - and more successful than - Roslin's. ""We wouldn't try to just follow on what they did,'' says First.

These successes, preliminary as they are, have inspired a religious organization called the Raelian Movement to establish a company - Clonaid - to produce human clones for infertile or gay couples, singles or anyone who wants a genetic duplicate. Projected cost: about $200,000. (The Raelians, founded by a French auto-racing journalist, believe that humans were created by intelligent beings from another planet.) Fortunately or unfortunately, the Roslin Institute has said that if the Raeli- ans ask to license its proprietary clon- ing technique (which they have not), it will refuse.

But those opposed to cloning humans aren't so sure that cloning will stay firmly in the realm of science fiction. This month the White House sent to Congress proposed legislation that would ban the cloning of children. This week a conference in Washington will examine the ethical implications of cloning. It's com- ing none too soon. The partial success of experiments cloning sheep, rabbits and cows shows that Dolly was no fluke, and that the method that created her, or a modification of it, may work with all mammals. When it published the paper reporting the birth of Dolly, the journal Nature wrote that it would not be surprised to see a human cloned within 10 years. Given what scientists have learned in the ensuing three months, that statement looks circumspect.

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