Physical and psychological illnesses are considered the first stages of the disease, which can be depressing to those infected. Secondary illnesses, such as pneumonia, are often the actual cause of death (HDA.org). There is no treatment to halt the inexorable progression which leads to death after ten to twenty-five years (HDFoundation.org).
Experts estimate that one in every 10,000 persons- nearly 30,000 in the United States- has Huntington’s disease (HDFoundation.org). Juvenile Huntington’s disease, HD that develops before the age of 20 and progresses rapidly, occurs in approximately 60% of all cases. HD is not prevalent within any particular population. All races and ethnic groups, and both sexes can be equally affected (neurologychannel.com).
Huntington’s disease is caused by a faulty gene on chromosome 4. The gene, which produces a protein called Huntingtin, was discovered in 1993. “In some way-which is not yet understood- the faulty gene leads to a damage of the nerve cells in areas of the brain” (HDA.org). A genetic test is available from Regional Genetic Clinics throughout the country. This test will usually be able to show whether someone inherited the faulty gene, but it will not indicate the age at which they will develop the disease. This test, coupled with a complete medical history and neurological and laboratory tests help physicians diagnose HD. However, in one to three percent of individuals with HD, no family history of the disease is found (Ninds.nih.gov).
At this time, there is no way to stop or reverse the course of Huntington’s disease. Now that the HD gene has been located, investigators are continuing to study the HD gene with an eye toward understanding how it infects the human body (Ninds.nih.gov).
Currently there is no cure for the illness but there are many ways to manage the symptoms effectively. Medication can be used to treat symptoms such as involuntary movements, depression and mood swings. Speech therapy can significantly improve speech and swallowing problems. A high calorie diet can prevent rapid weight loss and improve symptoms such as involuntary movements and behavioral problems (HDA.org).
“Scientific investigations using electronic and other technologies enable scientists to see what the defective gene does to various structures in the brain and how it affects the body’s chemistry and metabolism. Laboratory animal are being bred in the hope of duplicating the clinical features of HD so that researchers can learn more about the symptoms and progression of HD. Investigators are implanting fetal tissue in rodents and non-human primates with the hope of understanding, restoring, or replacing functions typically lost by neuronal degeneration in individuals with HD” (ninds.nih.gov).
Scientists at the National Institutes of Health, in collaboration with a Medical Center neuropathologist, have genetically engineered and studied mice that mimic the behavioral pathological changes of Huntington’s disease. The development of a line of transgenetic mice that express the complete human HD gene are created by injecting foreign genes into the embryonic animals. (Young 1). “The animals’ cells then follow ‘instructions’ of the foreign gene. Transgenetic animal models are developed in an effort to duplicate human disease, with the goal of better understanding it development and studying potential treatments” (sciencedaily.com). The genetic defect that produces HD results when a particular sequence of DNA is abnormally repeated dozens of times. The more repeats of this sequence of DNA, the greater the odds that the person will develop HD.
“‘The mice develop early symptoms after eight to ten weeks, seen first as hyperactivity and some changes in posture.’ Dr. William Whetsell, professor of pathology and psychiatry at Vanderbilt said. ‘They become quite restless, then begin constant circling. After a time, they gradually slow down, become inactive and lose interest in their surroundings. Then they become virtually inert and die” (Manley 1).
Works Cited
Collins, Debra, MS CGC. “Genetics of Huntington’s disese.” Online Article. 19 February 2004. Available FTP: Hostname: al/huntingtons/genetics.html. University of Kansas.
Hereditary Disease Foundation. Online Article. Internet, February 17, 2004 Available FTP: Hostname: .
Huntington’s Disease Association Online FAQs. Internet, February 15, 2004 Available FTP: Hostname: .
Hereditary Disease Disorders. Internet, February 15, 2004 Available FTP: Hostname: huntington.html.
Neurological Diseases and Disorders. Internet, February 17, 2004 Available FTP: Hostname:
List of Genetic Disorders and Resources. Internet, February 15, 2004 Available FTP: Hostname:
Manley, Cynthia. “Genetic Engineering Aids Huntington’s Disease Research.” Online Article. genetic.htm
Young, Luther. “Huntington’s Disease Mouse Model To Be Distributed By Jackson Laboratory.” Online Article. Available FTP: Hostname: http://
“Mouse Model For Huntington’s Disease Developed by NIH, Vanderbilt” Online Article. February 23, 2004, Available FTP: Hostname:
Johnson, George B. and Raven, Peter H. Biology: Principles and _ Explanations. Austin: Holt, Rinehart and Winston, 1998
