Cloning and concerns about itCloning in biology is the process of producing similar populations of genetically identical individuals that occurs in nature when organisms such as bacteria, insects or plants reproduce asexually. Cloning in biotechnology refers to processes used to create copies of DNA fragments (molecular cloning), cells (cell cloning), or organisms. Molecular cloning refers to the process of making multiple molecules. It is used in a wide array of biological experiments and practical applications ranging from genetic fingerprinting to large scale protein production. Cloning of any DNA fragment essentially involves four steps. First is fragmentation – breaking apart a strand of DNA; second is ligation - gluing together pieces of DNA in a desired sequence; third is transfection - inserting the newly formed pieces of DNA into cells and the last is screening or selection - selecting out the cells that were successfully transfected with the new DNA. Cloning a cell means to derive a population of cells from a single cell. In the case of unicellular organisms such as bacteria and yeast, this process is remarkably simple and essentially only requires the inoculation of the appropriate medium. However, in the case of cell cultures from multicellular organisms, cell cloning is an arduous task, as these cells will not readily grow in standard media. Organism cloning (also called reproductive cloning) refers to the procedure of creating a new multicellular organism, genetically identical to another. In essence this form of cloning is an asexual method of reproduction, where fertilization or inter-gamete contact does not take place. Asexual reproduction is a naturally occurring phenomenon in many species, including most plants (vegetative reproduction) and some insects. Scientists have made some major achievements with cloning, including the asexual reproduction of sheep and cows. There is a lot of ethical debate over whether or not cloning should be used. However, in the United States, the human consumption of meat and other products from cloned animals was approved by the FDA (The Food and Drug Administration) on December 28, 2006, with no special labeling required. Cloned beef and other products have since been regularly consumed in the US without distinction. Because of recent technological advancements, the cloning of animals (and potentially humans) has been an issue. The Catholic Church and many religious organizations oppose all forms of cloning, on the grounds that life begins at conception. They concern about the protection of the identity of the individual and the right to protect one's genetic identity. Another concern is that the biotechnologies used on animals may someday be used on humans. Researchers have found several abnormalities in cloned organisms, particularly in mice. The cloned organism may be born normal and resemble its non-cloned counterpart, but majority of the time will express changes in its genome later on in life. The concern with cloning humans is that the changes in genomes may not only result in changes in appearance, but in psychological and personality changes as well. The theory behind this is that the biological blueprint of the genes is the same in cloned animals as it is in normal ones, but they are read and expressed incorrectly. Results of these abnormally expressed genes in the cloned mice were premature death, pneumonia, liver failure and obesity.
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