Essay A Brief Discussion of Genetic Diseases

2240 Words9 Pages
Since the discovery in 1928 via the Griffith experiment (an experiment dealing with bacterial transformation) that DNA carried genetic information, many important discoveries have been made regarding the human genome and its extent in the determination of phenotypic traits. Not least of these is the discovery and study of genetic disorders, or diseases caused by abnormalities within the genes. Disorders of this nature can be caused by a variety of factors. Some diseases such as Huntington's disease must be inherited, while others, such as some cancers, can be the result of environmental factors slowly mutating the genome over time. Still others can result from random errors in normal DNA replication. Typically, genetic…show more content…
In more advanced cases, cancerous cells can exhibit metastasis, a process in which the cells spread to multiple other parts of the body. At this point in the disease, survival of the patient becomes much less likely. Cancer can affect any part of the body, but it is more common in areas of the body that are regularly exposed to outside influences that may lead to mutations, resulting in cancers such as lung, skin, and lymphatic cancers (National Cancer Institute). Cancer is believed to be caused primarily by environmental factors. This would include, for example, UV light from the sun, which can cause dimerization of thymine nucleotides ultimately leading to mutations causing skin cancer. Similarly, mutagens in cigarette smoke are involved in causing lung cancer. However, more recent studies show that predisposition to cancer is inheritable. The logic to this lies in the mechanism in which cancer develops. For cancer to develop, a single cell in the body must be mutated so that it undergoes continuous and uncontrollable cell division without the ability to exhibit apoptosis (i.e. programmed cell death for the good of the organism). In order to gain these abilities, a series of genes must mutate simultaneously within the cell. First, a class of genes called oncogenes must be turned on to express themselves at high levels. Activation causes the loss of apoptosis ability and accelerates cell growth and cell division. In addition, another class of
Open Document