The term cloning describes a number of different processes that can be used to produce genetically identical copies of a biological entity. The copied material, which has the same genetic makeup as the original, is referred to as a clone.
Yes, natural cloning can occur when a fertile egg splits, creating two embryos, but genetically they are the same, thus making it a clone. Pretty much, if you see identical twins, one of them is a clone.
The other name for gene cloning is known as DNA cloning. DNA cloning is a very different process from reproductive and therapeutic cloning. Reproductive and therapeutic cloning share many of the same techniques, but are done for different purposes.
While cloning an animal, researchers remove a mature somatic cell also known as a skin cell, from an animal they wish to copy. The DNA is then transferred from a somatic cell into an egg cell, or oocyte. The DNA-containing nucleus is then detached. There are two ways the DNA can be added to the somatic cell. The first way is that they remove the DNA-containing nucleus of the somatic cell with a needle, then inject it into an empty egg. The second way, the doctors use an electrical current to fuse the entire somatic cell with the empty egg. In both ways, the egg will develop into an early stage embryo in the test tube and then is implanted into the womb of an adult female animal.
There have been many mammals cloned over the last 50 years including cats, deers, dogs, horses, mules, oxes, rabbits and rats. In my opinion, cloning rats was the most surprising to me because it is such a little animal that the precision required in the procedure is so high.
The spindle proteins are located very close to the chromosomes in primate eggs. These proteins are essential to the cell division process. When removing the egg’s nucleus to make room for the donor nucleus, it also removes the essential spindle proteins, thus interfering with the cell division process.
While cloning animals, a cat for example, the cloning process doesn’t directly affect the way a cat’s coat of fur turns out. That has to do with whether or not certain sex chromosomes are activated, which certain colour genes to be turned on or off. Therefore, even if the cat has the exact same genes, it’s not certain that their appearance will be identical.
Genetically modifying an organism can possibly produce certain proteins in the said organism’s milk that can help humans clot blood better. Another application of cloning is to test animals with certain modified genes to see how they counter certain diseases and such. In summary, cloning animals can be used to better human knowledge of how certain things like diseases react with certain genetic profiles, or to produce something that can be compatible with humans to help us with said diseases.
Most cloned animal embryos cannot develop into healthy individuals. Cloning has a very low efficiency, combined with safety concerns, presenting a serious obstacle to the application of reproductive cloning. Cloning also can cause a variety of defects in vital organs, such as the liver, brain and heart. As cells go through their normal rounds of division, the tips of the chromosomes, called telomeres, shrink.