How Dolly the Sheep Changed the World
Ten years ago, the world's first cloned mammal was born. Dolly the sheep proved that it was possible to take a cell from a specific adult animal, and then use that cell to make a genetic copy of that adult animal. Dolly also suggested that, someday, it might be possible to clone humans.
STEVE INSKEEP, host:
Ten years ago today, in Scotland, a lamb was born. Dolly was the first cloned mammal ever born. It raised the possibility that if you could clone one mammal, maybe you could clone them all, including humans. NPR's Joe Palca reports on the implications ten years later.
JOE PALCA reporting:
The procedure for making a clone isn't all that complicated. You take the DNA from an adult cell and put it into an egg from which most of the DNA has been removed. You then coax the egg to behave as if it were fertilized. If it does, the resulting embryo will be a genetic copy of the adult animal. Put that embryo into a surrogate mother, and if everything goes well, you get offspring.
Ian Wilmut led the team at the Roslin Institute outside Edinburgh that created Dolly. Even though the steps are straightforward, Wilmut said, when interviewed ten years ago, that getting them to work was not.
Dr. IAN WILMUT (Embryologist, Roslin Institute): We transferred 29 eggs into a recipient (unintelligible), and one of them became a live lamb. So you can see it's a very exciting and encouraging result. The efficiency's are poor and there's a need for a lot more research.
PALCA: Dolly's birth came as a shock. True, scientists had successfully cloned amphibians, but the only success in mammals using cloning techniques came when scientists started with DNA from embryonic cells, which hardly counts.
Michael Roberts is a professor of veterinary science at the University of Missouri.
Professor R. MICHAEL ROBERTS (Professor of Veterinary Pathobiology, University of Missouri-Columbia): I think the real surprise to everybody was the fact that it came from an adult cell and that somehow or other this adult cell could be reprogrammed and then made to act as though it was completely youthful again.
PALCA: One of the Scottish team's key discoveries was to find the critical moment to extract the DNA from the living adult cell. Armed with that knowledge, scientists began cloning everything in sight.
Dr. ROBERTS: Rabbit, horse, cow, goat…
PALCA: Pigs, cats, dogs, mules and, oh, yes, mice were cloned, too. For some, it was just too tempting not to try applying the technique to humans. In 1998, Chicago physicist Richard Seed was among the first to publicly jump into the human cloning arena.
Dr. RICHARD SEED (Physicist): It was my objective to set up a human clone clinic, make it a profitable fertility clinic…
PALCA: Seed's plans caused a national uproar. But, in the end, they came to nothing.
Then there was the fringe religious sect known as the Raelians. Brigitte Boisselier made this dramatic announcement on December 27, 2002.
Dr. BRIGITTE BOISSELIER (Scientific Director, Clonaid): I am very, very pleased to note that the first baby clone is born. She was born yesterday at 11:55 a.m.
PALCA: But Boisselier never presented any evidence she really had a clone, and most people think it's unlikely she does.
So far, it's proven notoriously difficult to clone primates. It hasn't worked in monkeys and no one has yet made a cloned human embryo. South Korean scientists claimed that achievement only to admit later that their work was fabricated.
The Korean scientists weren't the only ones trying to make human cloned embryos. Several scientific teams around the world are still trying, but their intention is not to make a baby; they want to make embryonic stem cells.
The ability to make cloned embryos means you could make stem cells tailored to an individual patient. These would, in theory, be ideal for stem cell-based therapies, since there would be no chance of immune rejection.
Dolly's creator, Ian Wilmut, has turned his research to this so-called therapeutic cloning. Wilmut is now working on ALS, a fatal neurological condition also known as Lou Gehrig's disease.
Dr. WILMUT: Since we've begun to speak about working on ALS, I've met a number of people who have the condition and it's a very unpleasant disease and there's nothing for it at the present time. So, as a non-clinician to have the possibility of contributing, albeit, something long-term to therapy, I find very exciting.
PALCA: One final note: why name the first cloned lamb Dolly? Well, the starting adult cell used to make Dolly came from the mammary tissue of a female sheep. Here's a musical hint, and I think we can leave it at that.
(Soundbite of Dolly Parton song)
Ms. DOLLY PARTON (Singer; Songwriter): (Singing) Folks back home think I'm a star now when they hear my records play…
PALCA: Joe Palca, NPR News, Washington. Transcript provided by NPR, Copyright NPR.