Junnie Charles
Pathophysiology: Huntington Disease
Florida International University
December 4th, 2014
Cellular level of Huntington Disease
Huntington disease (HD) is a progressive, neurodegenerative, autosomal dominant inherited disorder; a result of a mutation in the Huntingtin gene on chromosome 4. Characterized by profound physical, cognitive and mental deterioration, this disease is caused by a full penetrance mutant gene. Thus making it certain that the carriers of that mutant gene will develop the disease at some point in their lifetime.
Every child of an individual that carries the mutation gene which causes Huntington disease has a 50% risk of inheriting the disorder. Huntington Disease usually develops in the third or…show more content… Huntington Disease is caused by a specific gene mutation that influences the physical, mental and social functioning of affected individuals. According to Shirkon (2012) the normal Huntington protein appears to be crucial to the development of the brain for the early development of embryogenesis, the forebrain, and the survival of neurons in the adult brain which leads to the cognitive, psychiatric and physical complications seen in Huntington Disease. The signs and symptoms of Huntington Disease are usually subtle and may linger on for years before gradually increasing in its severity. The natural course of the disease from onset to death is estimated to be 15-20 years. The clinical signs and symptoms associated with this disease can be divided into three main categories. However, significant variation exists in the clinical manifestations of the individuals affected by Huntington Disease. Skirton (2012) clearly detailed the clinical signs and symptoms of Huntington Disease.
1. Physical complications include chorea, ataxia, incontinence, bruxism, dysphagia, dysphasia with hypokinesia, dystonia, bradykinesia, rigidity and dystonia are seen in the advance stages of the disease.
2. Cognitive complications include dementia with significant problem solving and decision making difficulties early during the disease…show more content… These genetic tests are used in four specific contexts. Direct mutation analysis may be ordered for individuals with signs and symptoms of Huntington Disease especially for those who have a family history of the disease; consent must be obtained prior to testing. Skirton (2012) adamantly believes that the individual being tested should be made aware of the increase in the risk status of immediate relatives that may be affected due to the results of the test.
Predictive testing is used when an individual who does not exhibit signs or symptoms of the disease is tested in order to discover if the mutation gene has been inherited. Predictive testing involves a series of pre and post counselling to facilitate the implications of the results whether positive or negative.
Pre-natal testing is used to test a fetus if one of the parents is positive for the mutation gene that causes Huntington Disease. This is performed by the extraction of DNA from the biopsy of the chorionic villi after twelve weeks of gestation.
Pre-implantation genetic diagnosis is used when the parents want to ensure that their children do not inherit Huntington Disease. The process entails the testing for the mutation gene from cells extracted from fertilized eggs via in vitro.
