Cloning In Biotechnology
The Future Impact on Human Life
Timeline
1938- First Idea Of Cloning
Hans Spemann was the first to purpose the idea of cloning. He called it a "fantastic experiment". His idea was to replace the nucleus of an egg cell with another cell nucleus in order to grow and embryo from an egg. (1)
1952- Cloning a Rana Pipiens Frog
Robert Briggs and Thomas King transferred the nucleus from an early embryo tadpole into a frog's egg in which the nucleus had already been removed. The resulting cell then developed into a tadpole but later on grew abnormally. However, the experiment did show that nuclear transfer was a possible cloning technique. The experiment also provided them with two new sources of information. First, the nucleus directs cell growth and the development of an organism. And second, that embryonic cells in early development are more useful for cloning than cells at later stages. (2)
1984-First Mammal Created By Nuclear Transfer
Steen Willadsen utilized a chemical process to separate a single cell from an 8-cell lamb embryo then used a small electrical shock to fuse it into an enucleated egg cell. After this procedure, the cell began to divide and after several days the lamb embryos were placed into the womb of a surrogate mother sheep. In result, three lambs were born. (3)
1996- Dolly The Sheep
Ian Wilmut and Keith Campbell cloned a lamb by transferring the nucleus from an adult's utter cell into an enucleated egg. This was a big deal due to how it was the first mammal to be cloned successfully from a somatic cell. (4)
2007- Rhesus Monkey
Shokhrat Mitalipov and his colleagues took a cell from an adult monkey and fused it with an enucleated egg. The embryo was then left to develop for some time, then its cells were grown in a culture dish. (6)
2018- China Clones Monkeys
Shanghai scientist cloned a long-tailed macaques monkey using the same technique as used with Dolly the sheep (somatic cell transfer). The monkeys were named Hua Hua and Zhong Zhong. (7)
