Much controversy has arisen around the cloning of humans and animals. Though cloning is not allowed within the United States, several foreign countries have pressed ahead in the study of cloning organisms. However, in order to clone an organism, its cell must be duplicated. In order to understand the problems many scientists face with cloning, you have to understand the process in which DNA is duplicated.
DNA, known as the blueprint of living organisms, has to literally be pulled apart in order for it to be duplicated. The elements of DNA must stay intact in order for the replication to work successfully. The elements of DNA include four nitrogenous bases (Cytosine, Guanine, Adenine and Thymine) held together by sugar and phosphate on the ends. If you have forgotten your high school biology basics, these bases must be paired in a certain way in order for the DNA replication to even be possible. Cytosine and Guanine (C & G) and Adenine and Thymine (A & T) must always be paired together. No exceptions.
Though the DNA strand eventually repairs itself, many enzymes must be introduced to the strand in order for the replication to begin. These enzymes include topoisomerase and helicase. Topoisomerase helps to unwind the tight strands of DNA, making it easier to be replicated. Though the strands have been divided, they will automatically try to come back together. This is when the enzyme helicase keeps the original strands from rejoining, making it easier for DNA replication to take place.
Elements of the original strand of DNA are present in the newly formed strands. This process is known as a semiconservative replication. This type of replication literally pulls the two sides of the DNA strand apart and divides them completely. The sides are left with incomplete bases that must find another matching half in order to complete the pair. As mentioned earlier, DNA can finish the duplication process by basically repairing itself. As the DNA splits itself in two, unzipping like a zipper, the exposed sides float freely in the cell itself. Within the cell are the “replacement parts” that are needed to complete DNA replication. These parts are the necessary bases for the DNA strands. Floating Cytosine, Guanine, Adenine, and Thymine flow to their lonely counterparts and complete the DNA puzzle. Along with the help of DNA polymerase, the pairs are united and form the new replicated strands of DNA. Other enzymes help to keep the space between the forming DNA strands clear while the bases reform the tight space of the original DNA strand and help the perfect the replication process.
Though the science of DNA replication is not under scrutinization, its end product is. Moreover, while the debate over the use of cloning continues around the world, all we can do is wait; wait to see what results from the war between science and morality in the coming years.
By Tamara C. Jude