New research techniques have made it possible to engineer and explore differences in the sets of chromosomes in organisms. This has been a technological revolution during the last decade. Allowing scientists to be able to explore DNA to a new extent. During the process of this research it has come apparent that foreign DNA inserted into self-replicating genetic elements such as bacteria plasmids can replicate. This breakthrough has also shown that the plasmids that have been used can also be used to change the genetic constitution of other organisms (1).
Through the process mentioned above there has been an increase in the methods in which DNA, Reproductive and Therapeutic cloning and the processes that happen in order for cloning to occur. DNA Cloning occurs when the DNA cell is replicated, an organisms DNA is taken and placed in a Vector also known as plasmid. This self-replicating cell will then create copies of the DNA code. After being placed into a foreign host cell that is suitable for the DNA the cell will then reproduced. Reproductive cloning in some aspects of the developing stages is similar but is still completely different. Reproductive cloning is the type of cloning that has successfully created the most famous clone to live. Dolly the sheep is famous as she was the first mammal to be successfully cloned from an adult cell. In 1996 Dolly was born. Reproductive cloning uses the process of somatic cell nuclear transfer shown in figure 1 below where the nucleus from an adult cell is taken and placed into a cell which has had its nucleus removed. Scientist use electrical currents or chemicals to stimulate the cell division process to begin and the embryo is then placed in a surrogate womb where it will stay till it is fully developed. Much like reproductive cloning Therapeutic Cloning uses somatic cell nucleus transfer. Therapeutic cloning goes through the same processes as reproductive but instead of making a whole new organism this is used to form stem cells. They take the nucleus from the somatic cell and then relocate it to an unfertilized egg which has had its nucleus removed. This cell then starts to develop and after 4-5 days it can then have the embryonic stem cells removed which can be used to make many other stem cells that are identical to the cell that the DNA was originally taken from.
Figure 1 - Cloning of somatic cells
Two organisms that are exact genetic copies of each other are clones. Although cloning does happen naturally, an example identical twins, the most common discussed topic of cloning is what happens in the lab. Somatic Cell Nucleus Transfer and Artificial Embryo Twinning are the two ways in which cloning can occur in the lab. Artificial Embryo Twinning process is just like natural processes of identical twin creation, but instead of the early stages of development when the embryo splits happening naturally, occurs in a petri dish in a laboratory. The fertilized embryo is developing in a petri...