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Biology

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Chromosomal Chaos and Cancer

Peter Duesburg, a professor of molecular and cell biology at the University of California, Berkeley, later arrived in Germany in 1964, where he successfully isolated the first true oncogene from within the Rous sarcoma virus. He was later elected to the National Academy of Sciences in 1986. Duesburg believed that mutations in individual genes are insufficient to cause the malignant transformations that are commonly seen in cancer.

As Duesburg began to study cancer in the early 1960's many scientists believed that viruses could be the cause for most malignancies. This suggestion was based on the discovery that tumor and leukemia producing viruses could infect host cells and insert genetic material into its genome. This act manufactures a cancerous transformation. In addition, for the past 30 years, research had been dominated by the theory that mutations in specific human genes are the source of all cancers. The demonstration of providing evidence for oncogenes that can only transform normal cells into malignant cells has proved unsuccessful. Duesburg explains how individual genes may possibly contain mutations, yet he notes that in case of cancer, chromosomes can be found duplicated, broken, scrambled, or have entirely missing parts to its structure. This can be viewed as the Ð''driving force' of cancer. The actuality that changes to the chromosome and its structure are factors enough to maintain malignancy. The author argues that these chromosomal mutations are enough to prompt unstable cells that further lead to the disruption of chromosomes and are responsible for the certain properties of malignant cells that are not explainable by the action of specific genes.

Duesburg and his research group came to the conclusion of a chromosomal theory of cancer. This theory was brought about by the fundamental biological characteristics that make an ordinary human cell normal. He states that nature, in addition with sexual reproduction is rather conservative with regard to chromosomes. An example such as Down Syndrome, demonstrates the systematic damage that results from the cause of having just one extra chromosome, number 21. They found that in cells that are aneuploid, the DNA content of a cancer cell, rose or fell either twice as much than that of a diploid cell or half as much. The enzymes that are supposed to help the repair or disposal of DNA would then be disrupted. Furthermore, Duesburg concluded a possible explanation for the reason cancer cells within the same tumor are able to exhibit different combinations. He reasoned that once aneuploidy is established, it is likely that there will be derangement of chromosomes.

Cancerous cells have a tendency to progress from bad to worse. The process of carcinogenesis is the process by which cells begin to develop their own sizes, shapes, and metabolic rates and growth. It is within this process that the cells are becoming worse and worse. Scientists have also found a challenge in discovering a theory that would explain how it is that normal cells can evolve to become so chromosomally unstable that it can produce a lethal cancer. In the late 19th century and early 20th century, two German scientists, David von Hansemann and Theodor Boveri made advancements in the research of caner cells. Von Hansemann discovered that all cancerous cells in fact carried abnormal chromosomes. On the other hand, Boveri, a biologist, that chromosomes are single handedly responsible for genetic

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