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Using the search to find the structure of DNA as an example, describe the main observations which led up to the classic description and the process by which the double helix structure was arrived at - Did this constitute a revolution in science?

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Introduction

Using The Search To Find The Structure Of DNA As An Example, Describe The Main Observations Which Led Up To The Classic Description And The Process By Which The Double Helix Structure Was Arrived At. Did This Constitute A Revolution In Science? The search for patterns of individual units of heredity, genes, started as early as the late 1800s when Gregor Mendel discovered a predictable transfer of characteristics from parents to offspring (Moore, 1963). From then until 1953 when Francis Crick and James Watson proposed the structure of DNA, which carries genetic information, it was an open field, many scientists were working on theories of its structure. It was only by postulating theories and disproving them that eventually a theory of the structure and description of DNA became established. I will try to account for the main observations which led to the description of the double helix and the process by which the structure was arrived at in this essay and also what effect the discovery had on genetic capabilities, scientific limitations and social risks - a revolution in science. The search to find heredity spanned tens of years. ...read more.

Middle

Around 1948, Maurice Wilkins became interested in the orientation of the bases in nucleic acids. A scientist, Rudolf Signer, visited London for a meeting and brought with him some highly polymeric DNA. He distributed samples of this to researchers, one of them being Wilkins. When Wilkins manipulated the DNA gel, he discovered fibres had been produced - "Each time that I touched the gel with a glass rod and removed the rod, a thin and almost invisible fibre of DNA was drawn out ..." (Portugal and Cohen, 1979, p238). He decided to study the fibres by X-ray diffraction analysis. With his colleague, Raymond Gosling, both scientists obtained an X-ray diffraction pattern of the structure of DNA. This was to be known as the A form of DNA. The key to obtaining the diffraction patterns was keeping the fibres of DNA moist. This technique was to be important to future studies. From the pattern of the A form of DNA, it became evident that the patterns exhibited helical characteristics and in 1951, because of this X-ray, Stokes, Cochran, Crick and Vand postulated that the helix was not a restricted arrangement of atoms but was "an extended cylinder with certain repeating symmetry characteristics" (Portugal and Cohen, 1979, p240). ...read more.

Conclusion

The implications of this technology are far reaching. The first mammal to be cloned from an adult was achieved in 1997, Dolly the lamb, and genetically modified food has been produced to withstand disease. Whilst the development of genetics can be extremely useful to, for example, countries that experience starvation and famine, concerns have arisen out of this new era of genetics and this knowledge, essential for the future of medical research, drug-related treatments and many other fields of science, whilst it is exciting it can also be perceived as dangerous. Regarding the manipulation of genetics, there are implications about the fairness in the use of genetic information by such institutions as insurers, or adoption agencies, for example. There are reproductive issues, should we use genetic information in reproductive decision making, for example, giving birth to a child whose bone marrow, or some other part of their make up, will save the life of its sibling? There are clinical issues, can genetic tests be evaluated and regulated for accuracy and reliability? There are many societal concerns arising from work in genetics. A revolution in science has begun. Hopefully, the aims of the Human Genome Project will be realised, and along the way, the ethical, legal and social issues (ELSI) that may arise from the project, and the new era of genetics, will be addressed. ...read more.

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