To start with, cloning is the creation of an organism that is an exact genetic copy of another. This means that every single bit of DNA is the same between the two. There are lots of discussions whether cloning is useful, harmful, risky or not, but usually such doubts come from beliefs, which are not correct, but widely spread among society. That is why I decided to discuss five common myths, which are related with cloning of animals.
Myth: Cloning is a new technology.
Actually, cloning isn’t new at all. In fact, we eat fruit from plant clones all the time, in the form of bananas and grafted fruits. We’ve been cloning plants for decades, except that we refer to it as “vegetative propagation.” It takes about 30 years to breed a banana from seed, so, to speed the process of getting fruit to market, most bananas, potatoes, apples, grapes, pears, and peaches are from clones.
Some animals can reproduce themselves by vegetative propagation, including starfish and other relatively simple sea creatures. Amphibians such as frogs first underwent cloning in the 1950s. Identical twin mammals can be thought of as naturally occurring clones, but producing clones of mammals in the laboratory is relatively new. Using cells from animal embryos to make clones has been around since the early 1990s, but the first animal cloned from a cell from an adult animal was Dolly the sheep, who was born in 1997.
Myth: Clones are a specific animal’s DNA grafted onto another body.
Absolutely not. Despite science fiction books and movies, clones are born just like any other animal. The only difference is that clones don’t require a sperm and egg to come together to make an embryo. Clone embryos are made by using a whole cell or cell nucleus from a donor animal and fusing it to an egg cell that’s had its nucleus removed. That embryo is implanted into the uterus to grow just as if it came from embryo transfer or fertilization.
Myth: Offspring of clones are clones, and each generation gets weaker and weaker and has more and more problems.
No, not at all. A clone produces offspring by sexual reproduction just like any other animal. A farmer or breeder can use natural mating or any other assisted reproductive technology, such as artificial insemination to breed clones, just as they do for other farm animals. The offspring are not clones, and are the same as any other sexually-reproduced animals.
Myth: Clones have exactly the same temperament and personality as the animals from which they were cloned.
Temperament is only partly determined by genetics; a lot has to do with the way an animal has been raised. It’s the old “nature versus nurture” argument.
For example a farmer wants to clone his horse because of his gentle and sweet temperament. Although his horse’s clone may be easy-going, he would have to have exactly the same life experiences as original horse in order to have the same temperament.
Myth: Cloning can cure diseases in livestock.
Cloning can’t directly cure diseases in livestock, but the cloning process may be one way to make a healthy copy of a valuable animal that has contracted a disease, been injured, or died. In addition, cloning may also be a way to duplicate a disease-resistant animal, and over generations create a disease-resistant herd.
All things considered, I would like to say, that cloning can not be good or bad by itself, it depends on purposes and ways in which it will be used.
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