- The Washington Times - Saturday, January 5, 2002

Dolly the sheep the first mammal cloned from a cell taken from an adult animal has arthritis, and that's an alarming setback for scientists striving to use cloning as a tool for developing revolutionary new medical cures.
Sheep are not immune to arthritis. But there are two major factors that make Dolly's newly discovered affliction unusual: At age 5, she is considered remarkably young to develop the condition; also, she has the arthritis in two hind-leg joints where the inflammation usually does not occur.
Announcing Dolly's condition to reporters in Scotland yesterday, Ian Wilmut, Dolly's "very disappointed" creator, said, "This provides one more piece of evidence that, unfortunately, the present cloning procedures are rather inefficient. This suggests it may be the result of a genetic defect caused by cloning."
He continued: "We know from our previous research that only a small proportion of embryos that we produce develop to become live offspring. Sadly, it seems one of the other outcomes from this will be that some of the cloned animals will prove to be more vulnerable to some diseases."
The arthritis discovery is important because researchers are hoping to clone healthy animals as a source of organs livers, kidneys, even hearts that can be safely and effectively transplanted into humans. This would relieve the chronic shortage of human organs for transplant and would spur development of a lucrative medical transplant business.
In fact, the U.S. branch of Britain's PPL Therapeutics the organization Mr. Wilmut works for and a joint venture between Biotransplant Inc. of Charlestown, Mass., and Switzerland's Novartis AG separately announced this week that it had cloned pigs created to provide transplant organs.
The cloned pigs represented a breakthrough because they were deliberately created with a genetic alteration. They were produced without the special gene that causes the body to reject alien organs. Thus it was thought the pigs' organs might be transplanted into human patients without fear that the patients' bodies would attack them.
The announcement yesterday raises the possibility that the organs of the newly created and seemingly healthy pigs may not be as problem-free as earlier believed.
Mr. Wilmut said it may be impossible to discover whether Dolly's arthritis is the result of some "unfortunate accident" or whether it was caused by the cloning process. Related to that mystery is the question of the sheep's actual age.
Dolly was born five years ago, but she was cloned from an 11-year-old animal. That leads scientists to ponder whether Dolly is genetically older than 5 and therefore susceptible to the arthritis.
"That's an interesting question and very complex to answer," says the Rev. Kevin FitzGerald, a molecular geneticist and professor at Georgetown University. "We're just starting to unravel the molecular pieces involved in the aging process." So, Father FitzGerald says, scientists still lack the knowledge to arrive at a conclusion on the question.
"We have strong evidence that cloning causes abnormal molecular events to occur in cloned animals that make it to birth. The molecular abnormalities cause a high rate of disease and illness and other problems."
Michael Watson, executive director of the American College of Medical Genetics, agrees. "It doesn't surprise me that they're finding problems. There are more problems with the cloning technique than people are aware of."
While troubled by Dolly's condition, Mr. Wilmut argued that further cloning research must go on.
"It is a technology with enormous promise for the treatment of degenerative diseases but we do need to be a little bit cautious," Mr. Wilmut concluded.


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