Molecular cloning, also called “recombinant DNA technology”, refers to the transfer of a single DNA to a self-replicating genetic element, to generate a large population of cells containing identical DNA molecules. In 1970’s, biologists isolated the DNA fragment containing the genes of interest and studied the genes from complex organisms individually. When the molecular cloning method is invented, they used restriction enzymes to isolate the genes from chromosomal DNA and then united with a plasmid isolated the genes. When the DNA fragment is joined with its cloning vector, then it can be reproduced along with the host cell DNA. The advance of molecular technology has been made in the genetic improvement of agricultural populations through artificial selection on chosen characteristics, which helps to develop superior crossbred through the combination of several improved breeds (Dekkers and Frederic Hospital).
Embryo cloning, also called “therapeutic cloning”, is the type of cloning technology people use in research. It is used to harvest any type of specialized stem cells in the human body, purposed to study human development in biomedical research and to invent new methods to treat diseases such as heart disease, Alzheimer's, cancer, and other diseases. Scientists hope that one day, organs and tissues can be cloned for the use in transplants by using therapeutic cloning. As a result, the need for organ donation could be significantly reduced. After all, thousands of challenges still have to be overcome before it becomes a reality.
Reproductive cloning is most commonly reported by the media, Rather than cloning human, it is the type of cloning technology “to generate an animal that has the same nuclear DNA as another currently or previously existing animal”(Cloning Fact Sheet). Dolly, the first mammal to be cloned from an adult DNA, was a mother of six lambs. She has proved that the nuclear transfer technology will not create a truly identical clone of the donor animal, only the clone’s nuclear DNA is the same as the donor. However, Dolly was only one success out of two hundred and seventy-six tries and the success rate is relatively low. With the improvement of this technology, reproduce genetically special animals for the study of human disease, and re-populate endangered animals become missions to the scientists.
The development of biotechnology has reached such a resplendent level, however, genetic engineering in particular, is one of the most controversial issues in debates, which is accused to “have placed the creation, control and shaping of life”(Almond, 7). The opponents claim that genetic engineering is unnatural and the ethics of it should be questioned. On the religious side, it is regards as “playing god” when one holds that creating human life is a job for God. When cloning another person, the cloned is being made in that one's image, not in God's. They claim that in vitro (test tube) fertilization is not “to have babies” in God’s image, but “to make babies” by picking the genes for their child. Furthermore, the cloned may be looked down