Science has made advancements in many fields. One of which is cloning. Have you heard of the famous sheep Dolly? Dolly was made from cloning procedure. She is identical to her mother. Well, now you must be wondering that we all look like our parents! But Dolly is a Xerox copy of her mother; in fact she is the identical sister of her own mother and Dolly doesn’t have a father! All this has been possible with the breakthrough in the cloning process.
Cloning : Definition
Cloning is the process by which an exact, identical copy of the original can be made. Clones are those organisms that have identical genes. That means the sequence of their DNA is the same- an exact copy. Identical twins or triplets are also called clones. When you take out the leaf of a plant and plant it somewhere else, it can grow into the copy of the original plant.
Our body is made up of very tiny organisms called cells. These cells do their usual work which the DNA tells them to do. The DNA stands for de-oxy-ribo-nucleic acid which is the genetic code in all human beings. A child gets this genetic code- half from the father and half from the mother. When a child is formed- it is formed from one single cell; the egg cell, which has the DNA from the father and the mother. This cell then divides itself into millions to form a child. This is known as differentiation. Each cell is a copy of the original cell and has the same genetic code.
How does Cloning work?
For the process of cloning, one only needs the egg cell. Scientists pull out the DNA from an animal cell and insert it into the egg cell. The egg cell is taken from another animal. The nucleus or the DNA from the egg cell is removed with the help of a very fine needle, before the implantation process.
Cloning Dolly the Sheep
Previously it was believed that once the cell started to differentiate it could not be used to produce an organism. It was a breakthrough for Scientists of the Roslin Institute in Edinburg, UK with the successful cloning procedure.
For cloning of sheep the udder cells were used. These are cells that are found in the female mammal’s udder or the milk glands. Thus, one udder cell is then fused with the nucleus-free egg cell. The egg cell was from a black faced sheep, but the udder cell, with the DNA, was of a white-faced sheep. Scientists made 277 of these cells for their experiments. These cells were then fused into several different sheep. Out of all the 277 sheep, only one was able to develop into a lamb. It was named Dolly who was born on July 5, 1996. Dolly had the same white face as the sheep from which the udder cell was taken. She had the exact same DNA as the udder cell donor. Dolly is the clone of the udder cell donor. Later Dolly gave birth naturally to a lamb named Bonnie. Dolly died at the age of six due to a lung disease. People think that it was because of the cloning process but scientists disagree.
After this, scientists in Hawaii Laboratory conducted experiments on mice, using cumulus cells which are a type of cell found in the ovaries. They cloned the mice and the donor gave birth to Cumulina, the clone.
Scientists have thought of cloning human beings, but such an experiment hasn’t been conducted yet as there are several laws banning human cloning. Cloning can be seen in the movie Jurassic Park where clones of Dinosaurs were made from their DNA.
5 Facts about Cloning
- Cloned animals age faster than normal, original animals.
- Catholic religion is against cloning.
- Scientists are trying to save some endangered species with the help of cloning process.
- Japanese scientists are trying to bring back the Mammoth using the cloning technique.
- Ruppy and five other puppies are dogs that glow in the dark. They are created by scientists in South Korea. Its genes are taken from sea anemone, water dwelling animals and scientists replaced the mother dog’s egg cells with special glowing dog stem cells.
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