University of Phoenix
February 6, 2011
Rex Philpot, Ph.D.
The human body in its ability to function properly is comprised of the central nervous system, the peripheral nervous system, and the autonomic nervous system, which is a “branch of the peripheral nervous system” (Carlson, 2010, p. 97). The central nervous system and the peripheral nervous system make up the primary controls that command all physical movements. The neurons of the central nervous system affect consciousness and mental activity, which include skeletal muscles and bodily organs (health-care.net, 2005). Neurological disorders are disorders that affect the central, peripheral, and autonomic nervous systems. Neurological disorders are diverse, chronic, challenging to treat, and often disabling. An example of one neurological disorder is Huntington’s disease (HD). To begin to understand HD, which currently inflicts 15,000 Americans (National Institute of Neurological Disorders and Stroke, 2010), it is first imperative the one understand the basis of this disease and the symptoms and functional defects associated with HD. It is also important to know if there are biological and environmental factors that implicate the onset of this disease as well as any cognitive and pharmacological therapies used to reduce the symptoms or slow the progress of HD. HD is diagnosed via a physical and neurological examination. Blood tests can screen for the genetic abnormality. Everyone who carries the gene will eventually develop HD. The Neurological Basis of Huntington’s Disease
An American physician noted huntington’s disease named, George Huntington, in 1872. HD is a universal disease found in every country in the world. HD is also a family disease passed from parent to child through a mutation in the normal gene. HD is a progressive disorder that involves degeneration of nerve cells in the brain. A single abnormal gene produces HD. Genes are made up of DNA molecule, shaped like a spiral ladder. Each step of this ladder is composed of two paired chemicals called bases. There are four types of bases, adenine, thymine, cytosine, and guanine. The first letter of each bases is used to identify them, A, T, C, and G. Certain bases always pair together, and different combinations of each pair join to form coded messages. A gene is representative by this long string of DNA molecules, which, in turn, consist of various combinations of A, T, C, and G. These unique combinations determine the genes function, very similar to the way letters join to form words. Every human being has approximately 30,000 genes and a billion base pairs of DNA (bits of information) repeated in the nuclei of each cell. These base pairs of DNA determine individual characteristics and traits. These genes are positioned along the 23 pair’s chromosomes. One chromosome from each pair comes from the mother and one chromosome from each pair comes from the father. The gene that produces HD is on chromosome number four placing men and women at equal risk of inheriting the disease (National Institute of Neurological Disorders and Stroke, 2010). The affect of a gene depends, partly, on whether the gene is dominant or recessive. If a gene is dominant, then only one of the paired chromosomes is required to produce the effects of the gene. If the gene is recessive then both parents must provide chromosomal copies for specific trait to be present. HD is referred to as an autosomal dominant disorder because only one pair of the defective gene, inherited by one parent, is necessary to inherit the disease (National Institute of Neurological Disorders and Stroke, 2010). The disease is caused by a defect in a gene known as, huntington. The defective gene (huntington) contains 40 or more DNA nucleotides compared to 30 DNA nucleotides found in a normal huntington gene (health-care.net, 2005). The extra...
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health-care.net, (2005). What 's Huntington 's Disease. Retrieved from http://neurology.health-cares.net/huntingtons-disease.php
National Institute of Neurological Disorders and Stroke. (2010). Huntington 's Disease: Hope Through Research. Retrieved from http://www.ninds.nih.gov/disorders/huntington/huntington.htm
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