Cloning not difficult, scientists say, but too much can go wrong

Knight Ridder/Tribune News Wire, Dec. 27, 2002
http://www.thestate.com/
BY BOB LAMENDOLA

FORT LAUDERDALE, Fla. – (KRT) – Look no further than Dolly the sheep to see the biological perils of cloning a human, researchers and doctors say.

Dolly was born in 1997 after 276 failed attempts that resulted in many disfigured and dysfunctional animals. Now, despite her normal beginnings, Dolly has developed unusually early arthritis that may be the result of a genetic defect during the cloning. Other cloned animals have had deformed brains, hearts, lungs and blood vessels that led to premature death.

Scientists said the track record of cloning is still too scary for humans, even if the cloned baby girl Eve announced on Friday by the Clonaid company turns out to be healthy and truly a clone, which they doubt.

“You don’t want to experiment on human beings,” said Dr. Kimberly Thompson, an in vitro fertilization specialist at South Florida Institute for Reproductive Medicine in Pembroke Pines and Miami.

“It’s not that you technically could not do it; it’s not that complicated to do. It’s that you don’t know if you can produce a healthy offspring every time,” Thompson said. “Scientists don’t mind if something goes wrong with a cow or a sheep, but a human is different. The desire should be not to mess with human beings until you know what you are doing.”

That said, scientists believe that if the Eve cloning proves true, it could help open the door wider for research under way in which cloning techniques are used, not to produce a baby, but to produce cells to replace a weak heart or kidney, to erase cancer cells, to alter brain cells gone awry in Alzheimer’s disease.

“We’ve got a science that if handled appropriately offers exciting possibilities for medical care,” said Kenneth Goodman, a bioethicist at the University of Miami.

After Dolly was successfully cloned, the founder of the Raelian sect created Clonaid as a private, for-profit firm dedicated to cloning research.

Clonaid’s leaders said they have perfected the process that created Dolly. They took an egg from the human mother and removed the nucleus carrying the DNA, which is the body’s blueprint. They used an electrical current to fuse the empty egg with the mother’s skin cell carrying her own genes. Clonaid implanted the embryo into the mother’s womb, where it grew to term.

The company says it implanted 10 women with clones. Five of them self-aborted within weeks, and following Eve, four other cloned babies are expected to be born in the next month or so.

Skepticism reigned among scientists asked about Clonaid’s clone, a claim that has not yet been biologically verified.

First, they doubted that a major achievement could come from a little-known company headed by principals of the Raelian religion, which holds that humans are clones of extraterrestrials. West Virginia officials who inspected a now-closed Clonaid lab called it rudimentary.

Other teams say they are close to cloning a baby, notably Italian scientist Dr. Severino Antinori and Kentucky-based Panayiotis Zavos, who operates overseas.

Even so, researchers said they doubted anyone had mastered a science that has proved elusive for a half-century.

Scientists first extracted the nucleus of a frog egg in 1952, raising the possibility that it could be transplanted into another cell. It took until 1975 to grow a tadpole clone that lived. Since Dolly – the first animal clone – labs have cloned mice, cows, pigs, goats, rabbits and cats.

Just 3 percent of cloned animals have been born alive, and some of those had defects. Scientists said the hard part of cloning is to avoid causing mutations of the genes, which happen in many ways not fully understood. That would be especially hard in humans, with 40,000 genes.

“When you get genetic mutations, you tend to get diseases,” said Dennis Steindler, a University of Florida researcher working with adult stem cells (not from embryos) in search of treatments for neurological diseases, such as Alzheimer’s. “One mistake and you get an effect.”

Researchers suspect – but don’t know for sure – that the defects in cloned embryos and in cloned animals after birth may be due to biochemical changes during the cloning process, or to interruptions in the normal timing of the way genes work together.

“I think it’s unlikely … that we could control genes enough to make sure a baby stays healthy,” Thompson said. “Medical problems develop even if the offspring are born appearing healthy.”

Informed scientific debate of Clonaid’s findings has been impossible, because the company has not disclosed its failures, the patients, who did the work, where it was done, or details of its methods.

Researchers said they feared that the fringe nature of Clonaid and its secretive history may scare Congress or state legislatures into banning any research involving cloning techniques, including those considered most promising for medical breakthroughs.

“This was not done in a controlled, scientific environment. It was a closed process,” Goodman said. “It was very troublesome. It will muddy the waters, confuse things for elected officials who are trying to make legislative decisions.”

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