October 22, 2012
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Huntington’s Disease Research Paper3-6
October 22, 2012
Huntington's disease (HD), or previously Huntington’s chorea, is a neurodegenerative genetic disorder that affects muscle coordination and leads to cognitive decline and dementia. It usually becomes noticeable in middle age. HD is one of the most common diseases that show chorea, or involuntary jerking or writhing movements. It is much more common in people of Western European origin than in those of Asian or African descent. The disease is caused by an autosomal dominant mutation on either of a person's two copies of a gene called Huntingtin. This results in any offspring of an affected parent has a 50% risk of inheriting Huntington’s. In the rare situations where both parents have an affected copy, the risk increases to 75%, and when either parent has two affected copies, the risk is 100%, which means that all children of those parents will have HD. Physical symptoms of Huntington's disease can begin at any age from infancy to old age, but usually begins in the mid 30’s through the mid 40’s. About 6% of cases start before the age of 21 years with an akinetic-rigid syndrome; they progress faster and vary slightly. The variant is classified as juvenile, akinetic-rigid or Westphal variant HD.
The symptoms of Huntington’s disease occur gradually over time, meaning there isn’t a sudden change to the body and thus, it is difficult for medical experts to when some symptoms start. Symptoms of the disorder are physical, cognitive or psychiatric. Symptoms vary from each person as some may have symptoms that show clearly and others more minutely. The physical symptoms of Huntington’s disease include a general lack of coordination and involuntary movements causing an unsteady gait (the pattern of movement of the limbs) and most people with Huntington’s disease show chorea sometime in their life while others experience stiffness, known as dystonia. Dysphagia also occurs because of the muscles used to speak and swallow do not synchronize correctly and can often result in choking and weight loss, although weight loss is also due to many other contributing factors. Huntington’s disease inhibits cognitive function and most of the victims with HD have difficulty planning or organizing tasks and have a habit to focus on one thought or action which in turn causes extreme difficulty while trying to focus on one task for a long period of time. Huntington’s disease is also commonly seen as other diseases by the general public because those suffering with HD have a diminished impulse control which can cause outbursts, depth and spatial perception issues, and difficulty trying to process thoughts or learn new information. These symptoms could be misconstrued by others into thinking it is a different disease altogether, such as those with an intellectual disability. The psychiatric symptoms are perhaps the most devastating as they can lead into many other disorders which could have hundreds of other symptoms that don’t immediately relate to HD, the most common being depression. Others include an increased rate in anxiety, hyper sexuality, aggression, and compulsions. With just a few symptoms, a person with Huntington’s disease can become very unstable, and depending on the severity, should be monitored with a health specialist.
Huntington’s was often misdiagnosed until technology could provide a MRI or CT image to give further evidence than word of mouth. In order to diagnose Huntington’s, a neurologist will interview the individual intensively to obtain the medical history and genealogy to rule out other conditions, as well as test the person's hearing, eye movements, strength, coordination, involuntary movements, sensation, movement, and mental status. To make a 100%