Huntington’s Disease
Personal Reference: Down in the Neurology department sat four family members patiently waiting for what seems to be a never-ending check up. As the doctor’s office door peaked open my mother and aunt both walked out with despairing eyes. When I looked up the doctor was handing my mother a best-known neurologist information card. At that moment silence broke out amongst us, as we knew a whole new life experience was on our hands. At age 34 my Aunt Eve was diagnosed with Huntington’s disease.

Background/Introduction: Huntington’s disease historical timeline indicates the first made known observation of the disease was by American physician George Huntington in 1872. Examining the symptoms and condition Dr. Huntington wrote a detailed account defining the hidden facts behind the disease. Yet it wasn’t until 1911 when Charles Davenport made major contributions in acknowledging and understanding the sings, symptoms and heritability of HD. The National Library of Medicine defines Huntington’s disease as a genetic degenerative disorder of neurons due to a defect in one part of the DNA. HD is recognized as a hereditary neurological disorder taking a devastating toll slowly diminishing an individual’s ability to speak, walk and reason. Because HD is a programmed genetic disorder its degeneration of nerve cells results in uncontrollable movements, emotional disturbance, and eventually memory loss.

Signs: Early onset signs of HD typically trail in three stages: Early-Stage HD, Middle-Stage HD, and Late-Stage HD. In the early stage HD individuals are diagnosed with a warning of symptoms but can still perform daily routine activities. Middle-Stage HD are developing signs such as losing the ability to perform certain activities and control muscle movements. In the final fatal late stage HD individuals loose the ability to speak and are bedridden. * Early Stage HD Signs: * Minor involuntary twitches * Difficulty thinking through tasks * Irritability * Middle Stage HD Signs: * Difficulty performing simple tasks (Eating, dressing, driving) * Involuntary “dance like” movements * Difficulty organizing thoughts and thinking clearly * Depression/ Losing interest * Late Stage HD Signs: * Unable to speak * Rigidity and Dystonia * Visual and Auditory hallucination * Bedridden

Symptoms: On average HD individual’s symptoms vary depending on family genetics. Regardless within each stage of HD motor, cognitive and behavioral symptoms slowly disappear. * Motor Symptoms: * Uncoordination * Chorea & Dystonia (Involuntary movements) * Difficulty balancing & speaking * Behavioral Symptoms: * Mood Swings * Depression * Anxiety * Cognitive Symptoms: * Loss of memory * Difficulty organizing thoughts * Concentrating

Anatomical/Physiological Structure Affected: The major cause of HD is degeneration of neuron in areas of the brain, specifically the cells located in the basal ganglia. Functions of the basal ganglia include motor control, cognitive and behavioral/emotional skills. The basal ganglia leads up to the cerebral cortex, which is responsible for memory, attention, and perception. The abnormal mutation gene in HD is identified as HTT gene. Scientists have discovered this gene repeats in one segment of the DNA known as CAG 36 to more than 120 times which is lethal since in a normal individual CAG is to be repeated 10 to 35 times within a gene. An increase in size of CAG produces an extremely long version of HTT. The elongated protein (HTT) is then cut into toxic fragments that bind and accumulate in neurons.

Diagnosis: Physicians usually perform a physical exam asking various questions concerning family medical history and testing motor and cognitive skills. Doctors may notice abnormal movements/reflexes and hear poor communication (can’t enunciate). PET scan (of brain), CT scan or MRI can be administered to show loss of brain tissue. HD can develop in adults as early as 30 years old and as late ad 55 years old. Genetics tests such as presymptomatic test is offered to individuals with HD in family history to identify if HD gene is evident.

Treatments: Currently no cure has been administered in treating Huntington’s disease and certainly no known methods can halt the disease from further progressing. The initial goal neurologists attempt to aid HD patients is by slowing down the symptoms. Particular medication can help depending on the severity of the symptoms and individual’s tolerance. For example: * Dopamine Blockers – reduce involuntary movements (not all patients respond) * Tetrabenazine – reduces overactive movements (has side effects of depression, dizziness, and anxiety).

Effectiveness of Treatments:
Effectiveness of HD medications are not 100% sufficient. Often several medical problems arise from HD such as infections taking a higher toll on HD patient’s health. Curing or slowing HD is an ongoing struggle researchers are attempting to solve.
Impact:
The different stages of the illness eventually terminate motor and cognitive skills thus an HD patient suffers from complete shutdown and terminally leaves an individual in 24-hour family care. HD individuals can no longer speak or chew must be fed through a feeding tube. Statistics/Future Research: Society of American Association estimates HD affecting one out of 100,00 Americans and will continue to be on the rise. A child with an HD parent will have 50/50 chance of inheriting the disease. If inherited HD individuals have 10-20 year life span. Today 200,000 Americans are at risk of HD. Since the 1990’s HD has attracted much considerable attention, “hope for research” is every HD patient’s wish. The Hereditary Disease Foundation has made significant efforts in funding research programs to better understand HD. Today molecular genetics scientists are well underway in interpreting and creating HD treatments.

References: 1. Standford Education. "Stages of Huntington's Disease." HOPES. N.p., 23 Aug. 2011. Web. 05 Feb. 2014.
<http://www.stanford.edu/group/hopes/cgi-bin/wordpress/2011/08/stages-of-huntingtons-disease/#symptoms-1>.
2. Huntington's Disease Society of America. " What Is Huntington's Disease?" Huntington's Disease Society of America. N.p., n.d. Web. 05 Feb. 2014. <http://www.hdsa.org/about/our-mission/what-is-hd.html>. 3. "Huntington's Disease." New York Times. N.p., 01 Jan. 2012. Web. 6 Feb. 2014. <http://www.nytimes.com/health/guides/disease/huntingtons-disease/overview.html>.

Discussion:

April, (Mine)
Thank you for your kind words.
I am glad you mentioned Parkinson’s disease. Throughout my research several journal articles mentioned Parkinson, Alzheimer’s, and Huntington’s disease to be a progressive diseases. Very often in Parkinson and Alzheimer’s symptoms come in a mild fashion and progress. Huntington’s and Parkinson are similar in that both a form of neurodengerative disease. Now, I did come across “gastrointestinal disorders” as a symptom of Huntington’s disease, but neurologists have observed that this symptom isn’t existent with every patient. Some patients experience a severity of constipation yet others seem not to have this issue. I chose not to mention mostly because I wanted to reflect on the most common symptoms all HD patients will face. In the cases that patients experience this most often physicians attempt to change the individual’s diet.
I am glad you did mention it though.

Carlos, (another)
Great job on your paper.
I took a personal interest in your paper because I too know several people with Asthma and I myself have had a minor case of asthma.
I am highly allergic to pollen, dust, and several types of trees (Oak and Maple). I developed Asthma when I was 9 years old and it stayed with me until 13 years old. I am certainly not clear on what happened but I slowly developed out of it. Which seems quite strange I know since I am still allergic to everything I mentioned above. My pediatrician at the time informed my mom that a human body takes a lot of developing up until 21 years of age. In my case I am 24 years old I am not as highly allergic to certain things as I was before, I certainly still am allergic but not as the severity as I had it.