Discovery of DNA Structure
Introduction
Discovery of DNA was a landmark period in science history that generated further tremendous discoveries. Thanking to this groundbreaking discovery, it was possible to explore the impact of genetic information on the diseases, behavior, and personality. While there are a lot of disputes around the link between DNA and personality features or the ability to create lively beings with the help of DNA mapping, the discovery of the double helix structure opened the doors to the unimaginable dimensions of scientific abilities. It is believed that DNA has been discovered by James Watson and Francis Crick in the 1953, but there was also the contribution of Rosalind Franklin, Maurice Wilkins, and Linus Pauling who made this discovery possible (Frank-Kamenetskii, 1997).
Discussion
However, as it was later revealed, the history of DNA discovery dates back to 1869 when a chemist Friedrich Miescher first revealed a particle that he called “nuclein” within the nuclei of a blood cell (Aronson, 2007). Later on, “nuclein” will be renamed as “nucleic acid” and further on as DNA. However, initial Miescher's aim was to isolate and explore the white blood cells rather than the “nuclein”. As the main method for collecting the data Miescher planned to utilize used pus-coated bandages taken from the hospital; he aimed to wash them and isolate the white cells for the further analysis.
After the scientist realized that he has isolated a new particle that had chemical characteristics different from other protein, Miescher came to a conclusion that he made a breakthrough in the chemistry (Clarke, 2007). Feeling that the results of his experiment were substantial, Miescher claimed that “it seems probable to me that a whole family of such slightly varying phosphorous-containing substances will appear, as a group of nucleins, equivalent to proteins” (Clarke, 2007). Unfortunately, Miescher's discovery was not appreciated in the scientific community, which made it possible for the future generation of scientists to make a breakthrough.
More than 50 years have passed before the discovery of DNA was finally appreciated, but the name of the scientist who was first to isolate it was forgotten for many years. While the scientific community was already aware about DNA, yet its structure remained a mystery for the majority of scholars. In the 1940’s, some scholars thought that DNA was a so-called “the molecule of life”, the others were still skeptical about it (Aronson, 2007). It was also revealed that DNA contained certain elements, particularly adenine, guanine, cytosine, and thymine, however, scholars did not know how DNA was structured. Watson and Crick, who were later on awarded with the Nobel Prize, implemented a method that did not initially produced positive results. According to the researchers, they utilized “stick-and-ball models to test their ideas on the possible structure of DNA, while the other scientists used experimental methods instead” (Menditto & Kirsch, 1983, p. 26).
As it was noticed earlier, Rosalind Franklin and Maurice Wilkins used an effective method of X-ray diffraction to determine how DNA is physically structured (Sayre, 1975). Franklin and Wilkins shined X-rays on the molecule of DNA, which managed to form crystals; than the invisible to naked human eye rays bounced off the molecule. After, the rays generate a set of complicated specimens transferred to photographic film (Sayre, 1975). By observing these specimens, the scientists managed to reveal important features of the physical structure of DNA. Franklin produced a famous “picture 51” that later on became the main evidence of true DNA structure.
In 1953 Linus Paulin tried to present his vision of the DNA structure and has published a paper where he claimed that DNA had three-helix structure. Watson and Crick came to the same conclusion by working with the Franklin’s pictures. However, all scholars got it wrong due to various mistakes made in the analysis of the pictures. According to the resources, the limitation was Watson’s fault, who misinterpreted the Rosalind Franklin’s explanation of her X-ray crystallographic method (Sayre, 1975). Particularly, Watson managed to make several mistakes in his notes when he was writing down Franklin’s explanation. Later in 1953 Instead, to Watson and Crick analyzed “picture 51” made by Franklin and came to an important conclusion that DNA has a double-helix structure (Menditto & Kirsch, 1983). “Picture 51” was different from the other ones made by Franklin because it was crystallized in the moist conditions, which revealed one X within the DNA, which identified double- helical pattern (Menditto & Kirsch, 1983).
The information retrieved from the “picture 51” enabled Watson and Crick to determine paring rules in the structure of DNA. In February 1953 Watson managed to recognize that the adenine-thymine link was absolutely of the same length with the cytosine-guanine bond. According to the researchers, “if the bases were paired in this way, each rung of the twisted ladder in the helix would be of equal length, and the sugar-phosphate backbone would be smooth” (Sayre, 1975, p. 39). In the results, Watson and Crick were awarded with the Nobel Prize for their tremendous contribution to chemistry.
The studies of DNA revealed tremendously important information since the fist transcription of the cells. Since that time genetics were raising important and yet controversial questions claiming people’s conduct depend more on biology, than on the socio-environmental factors. Linking DNA and particular behavior is still an issue requiring additional studies and multiple evidence to be absolutely true. However, not only genetics might be responsible for certain behavior, biological impairments can cause one’s brain to conduct in a particular way. Such acclamations usually contradict conventional theories about the pernicious influence of the surrounding environment. In the terms of criminology, such breakthrough requires detailed evaluation and analysis.
The studies in direction of linking human intelligence and IQ are still considered a controversial question. There are scholars claiming that IQ can be transferred from generation to generation only through particular genes. As the result, some evidence suggests that poverty can be derived from the low intelligence, yet these principles are not supported by the majority of scholars. However, for the last years scientists have found the way to isolate DNA consequences. “With these new tools, some scientists now are searching for biological explanations to far more complex phenomena, such as sexuality, risk-taking and violence. (Menditto & Kirsch, 1983, p. 29).” It gives criminology new material to research the problem of the reasons of violence from the other point of view. There are also studies aimed to prove that the type of temper is the responsibility of particular genes.
Further studies recognized the link of genetics and such disorders as schizophrenia, psychosis, and manic depression. As the result of such studies, criminology receives an opportunity to explain violence and misconduct from the point of biology. Additionally, biological point of view towards human conduct can be connected to social studies in this direction. According to studies the relation between genes and environment including its correlation and interaction is not random (Walsh & Beaver, 2009). Wanting that or not but each of human being bears the genetic traits of his or her ancestors presupposing particular behavior. However, in the case of adoption it is supposedly possible to rule out the idea that certain patterns of behavior are related to the adopted parents.
Modern studies continue to confirm that crime runs in families. As the practice shows, parental criminal activities usually influence their offsprings to walk the same road. Twin studies claim that Monozygotic twins are more likely to engage in crimes together than Dizygotic twins even if they are sharing the same environment. In this case, researchers supporting biological explanation of behavior have the reasons to claim their point is justified by the studies. One more type of studies addressing the nature versus nurture issue is adoption research. According to scholars, children use to follow the patterns of behavior of their biological parents rather than adoptive ones.
A genotype X environment interaction can be defined as the alteration in the relative performance of two or more genotypes evaluated in two or more environments. Interactions of any kind can trigger the changes of genotypes within selected environments. Such interaction refers to instances where the linked effect of genetic and environmental risk factors is significantly bigger comparing to the sum of separate effects. Scientist researching genetic influences on behavior among members of a family have differentiated between environmental effects that are shared by siblings brought in the same family and environmental impacts that differ for those siblings.
Conclusion
The significance of DNA discovery is tremendous, as it gave tons of possibilities to the scientists. It created the ability to treat many diseases, have the insight into the heredity, explain human behavior, and map human genome. The disciplines like genetic engineering, DNA profiling, criminology, medicine were enriched with the knowledge on human DNA structure and its impact on the organism. While there are a lot of disputes that surround such implementation of this discovery, as using stem cells or genetic engineering due to the ethical controversies, it is quite clear at this point that the outcome of the groundbreaking discovery was quite efficient for science and society in general. Thanking to the works of Franklin, Wilkins, Pauling, Watson, and Crick, modern science enables the couples to have children if there are problems, treat illnesses and even predict their occurrence, explain the level of IQ and behavioral patterns.
Bibliography
Aronson, J. D. 2007. Genetic Witness: Science, Law, and Controversy in the Making of DNA Profiling. New Brunswick, NJ: Rutgers University Press.
Clarke, G. 2007. Justice and Science: Trials and Triumphs of DNA Evidence. New Brunswick, NJ: Rutgers University Press.
Frank-Kamenetskii, M. D. 1997. Unraveling DNA: The Most Important Molecule of Life. Reading, MA: Perseus Publishing.
Menditto, J., & Kirsch, D. 1983. Genetic Engineering, DNA, and Cloning: A Bibliography in the Future of Genetics. Troy, NY: Whitston.
Sayre, A. 1975. Rosalind Franklin and DNA. New York: W. W. Norton.
Walsh, A. & Beaver, K. M. 2009. Biosocial Criminology: New Directions in Theory and Research. New York: Routledge.
