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20 Years Since 'Dolly'
It was 20 years ago this week that scientists announced the first successful cloning of a mammal — the now-famous sheep Dolly — from a cell taken from an adult animal. [Full story: 20 Years After Dolly the Sheep, What Have We Learned About Cloning?]
The cloning of Dolly by the team at The Roslin Institute, at the University of Edinburgh in Scotland, paved the way for researchers to try cloning a number of other mammals. Prior to Dolly, scientists had been able to clone mammals only by splitting growing embryos.
Since the announcement of Dolly's birth, dozens of other species have been cloned from adult body cells, including many mammals. Here are eight of the mammals that have been cloned in this manner since Dolly:
PigsSlide 2 of 17
In 2000, PPL Therapeutics, the same company that worked with The Roslin Institute to clone Dolly the sheep, announced that it had cloned five female piglets from adult pig cells. The piglets were named Millie, Christa, Carrel, Dotcom and Alexis. The findings were published in a 2000 paperin the journal Nature.Slide 3 of 17
CatsSlide 4 of 17
In 2001, researchers at Texas A&M University cloned a cuddlier animal: a cat. The kitten was born Dec. 22, 2001, to a surrogate mother, according to the findings, which were published in a 2002paper in Nature.
Though the kitten — nicknamed CC, short for Carbon Copy — was genetically identical to the cat Rainbow, the patterns on her fur looked different, likely due to developmental, rather than genetic, factors, the study said. CC had her own kittens a few years later.Slide 5 of 17
DeerSlide 6 of 17
Researchers at Texas A&M also cloned a white-tailed deer, nicknamed Dewey, in 2003. Dewey was born to a surrogate mother named Sweet Pea on May 23, 2003, and was cloned from skin cells taken from a deceased white-tailed buck, according to a statementat the time from Texas A&M University. Dewey is still alive today.Slide 7 of 17
HorsesSlide 8 of 17