Animal Cloning

by Kahleah du Toit, and Maria Dobroskok

What Is Cloning

In the process of cloning, the scientists extract the DNA from an animal cell and implant it into an egg cell taken from another animal.

Dolly The Sheep

Scientists at the Roslin Institute in Edinburgh, UK, made history on 27th February 1997, when they successfully cloned a sheep. Dolly. a Finn Dorset Sheep, was born on July 5th,1996. The DNA in her mother’s cell was removed and transferred into the egg cell of another sheep. Five months later, Dolly was born and is now a healthy lamb, a clone of her mother (from whom her DNA was taken) – and without a biological father. later that year the scientists who produced Dolly announced that they have created a lamb with a human gene in every cell of its body. Named Polly, the lamb was produced using a method similar to that used to create Dolly.

Frozen Mice, and Somatic Cell Nuclear Transfer

Since Dolly the sheep, reproductive cloning has continued to advance; nearly 20 different species have now been cloned. For example, scientists have produced 581 mice from an original donor mouse through 25 rounds of cloning. There were no abnormalities with the mice, even after repeated cloning. In 2008, Wakayama's team created clones from the bodies of mice that had been frozen for 16 years! To clone these animals, researchers use what’s called a somatic cell nuclear transfer.

• Extract an egg from a donor animal (donor A)

• Remove the nucleus -- which contains the genetic material (DNA) from the egg

• Insert a different animal's DNA into that egg (donor B)

• Implant that egg into a surrogate animal for development