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Cloning is the process of creating genetically identical copies of biological material. Cloning can reproduce both molecules, cells and tissues as well as whole organisms. It can be defined as a process of asexual reproduction of identical organisms or molecules. The term cloning derives from the Greek clone , which means twig, shoot or shoot and refers specifically to Botany, although in Spanish its use has been generalized to all biological materials.
There are three different types of cloning. Molecular cloning , also called gene cloning, produces identical copies of the DNA (deoxyribonucleic acid) molecules that make up chromosomes. Organism cloning or reproductive cloning involves making an identical copy of a complete organism. Therapeutic cloning generates human embryos that produce stem cells that are used to treat diseases.
natural cloning
The mechanism associated with the generation of a new organism from the genetic information of an existing one is a common form of asexual reproduction in nature, since organisms such as amoebas and other unicellular beings reproduce in this way. Plants, algae, and fungi produce spores that develop into new individuals that are genetically identical to the original, barring mutations. Bacteria are capable of creating clones through a form of reproduction called binary fission, in which the bacteria’s DNA is replicated and the original cell splits into two identical cells.
Some forms of natural cloning are budding , which is reproduction from the formation of protrusions called buds on the body of the original organism which then break off and develop independently; fragmentation , which is the division into several parts of the body of the original organism, each of which generates a new organism identical to the parent ; and parthenogenesis , that is, the segmentation of an unfertilized ovum that occurs in flatworms, crustaceans, insects, amphibians, and reptiles. The formation of identical twinsin mammals it is also a form of natural cloning, and in this case two identical individuals develop from a fertilized egg.
artificial cloning
Artificial cloning refers to laboratory techniques used to produce an organism that is genetically identical to another. Animal clones are created by a process called somatic cell nuclear transfer . In this process, the nucleus of a somatic cell is removed and placed in an ovum from which the nucleus has been removed. A somatic cell is any type of cell that is not a sex cell.
There are several animals that have been cloned. Dolly the sheep was the first mammal to be cloned, and was created from the research of scientists at the Roslin Institute in Edinburgh, Scotland. She was born on July 5, 1996. More recently, in early 2018, a group of Chinese scientists reported that they had managed to clone monkeys (article presentation photo) following the same technique used to create Dolly.
One of the main biotechnological problems facing human cloning is that animal cloning processes are only successful in a very small fraction of attempts, between 0.1 and 3%; Furthermore, the animals that survive tend to have poorer health and a shorter life expectancy than naturally generated animals. Scientists have not yet discovered the cause of these problems, but it is presumed that they would also occur if human beings were cloned. On the other hand, the cloning of human beings raises a series of ethical and legal discussions that have not yet been settled.
Sources
Alistair Brown. Therapeutic Cloning: The Ethical Road to Regulation Part I: Arguments For and Against & Regulations . Human Reproduction & Genetic Ethics, Vol. 15, No. 2, 2015.
David Cyranoski. First monkeys cloned with technique that made Dolly the sheep . Nature 553: 387-388, 2018. doi.org/10.1038/d41586-018-01027-z
Enrique Ianez Couple. Ethical reproductive cloning . University of Granada, Spain. Accessed December 2021.
