All About . . . Cloning
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TAMU College of Veterinary Medicine
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"CC," a cloned cat
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A clone is an organism that has developed from a cell of just one other organism. This means it has the exact same DNA as its parent. Scientists have been able to clone mammals artificially. The most famous clone was a sheep named Dolly, born in Scotland in 1996. In February 2003, after developing arthritis and a lung disease, Dolly was euthanized ("put to sleep"). She was young by sheep standards, and scientists were not sure whether her bad health came from being a clone. Labs that have cloned other mammals, including cattle and goats, say that the ones that live to adulthood seem normal in every way they can measure.
In February 2002, researchers in Texas announced the birth of "CC" (carbon copy), the world's first cloned cat. CC has the same DNA as Rainbow, the cat she was cloned from. But they look different, because calico patterns are affected by growth in the womb, not just genes. They differ in other ways too. CC is playful and curious, while Rainbow is shy. CC is slim, while Rainbow is chunky.
Researchers are also trying to clone extinct animals -- such as the Tasmanian tiger and mammoths -- using DNA from specimens kept in museums or found frozen in glaciers. Most scientists say that cloning dinosaurs -- as in the movie Jurassic Park -- is probably impossible, however, because they won't be able to find remains with enough intact dinosaur DNA.
Is human cloning possible? Perhaps, but many people believe it would be wrong, for ethical reasons and because of the risk of health problems.
Ciencia: Todo sobre . . . La clonación (Spanish Version)