Genetics In Huntington's Disease

Huntingtin is a 350-kilodalton protein of unknown function that is mutated in Huntington's disease (HD), a neurodegenerative disorder. The mutant protein is presumed to acquire a toxic gain of function that is detrimental to striatal neurons in the brain. However, loss of a beneficial activity of wild-type huntingtin may also cause the death of striatal neurons. Here we demonstrate that wild-type huntingtin up-regulates transcription of brain-derived neurotrophic factor (BDNF), a pro-survival factor produced by cortical neurons that is necessary for survival of striatal neurons in the brain. We show that this beneficial activity of huntingtin is lost when the protein becomes mutated, resulting in decreased production of cortical BDNF. This

Huntington’s disease destroys the organs that carry the functions of the central nervous system. Kalat (2013) states, “Huntington disease (also known as Huntington disease or Huntington’s Chorea) is a severe neurological disorder that strikes about 1 person in 10,000 in the United States” (A.B. Young, 1995, p. 258).Individual’s develop the symptoms in their middle age, but even if it is a rare disorders juveniles as well as children before the age of ten can develop the disease. Huntington’s disease is hereditary disease that is passed on from a parent. Huntington’s disease is of the lack of the chromosome 4, if one of the parents carries the gene, they can pass that gene to their

Huntington's Disease (HD) is an autosomal dominant, progressive, neurodegenerative disorder (Walker, 2007 and Harmon, 2007). The gene that causes the disease is located on the fourth chromosome and causes an abnormal number of repeats in the patient's genetic code (Harmon, 2007). Huntington's Disease can have devastating effects on patients' quality of life. The first symptoms of HD generally start between the ages of 30 and 45 and patients are typically asymptomatic prior to this time (Terrenoire, 1992 and Walker, 2007). However, the disease progresses with subtle changes in motor control, personality, and cognition. Patients eventually develop distinct

At present, there is no cure for the disease, but dynamic progress has been made as researchers explore this illness. HD is inherited as an autosomal dominant condition. In March 1993, scientists realized that HD is caused by a mutation in a gene located on chromosome 4. This gene has a unique genetic sequence for CAG (cytosine-adenine-guanine) and codes for the amino acid glutamine, a building block for the huntingtin pr otein. Normal individuals have this sequence duplicated from 11 to 40 times in their genetic coding without having symptoms of HD. However, individuals with the disease have from 40 up to 100 repeated CAG segments. Juvenile Huntington's Disease occurs wit h 60 or more repeats, linking the longer chains of CAG sequences to earlier and more aggressive onset of the disease.

Parkinson's Disease (PD) and Huntington's Disease (HD) are neurodegenerative diseases that are caused by malfunctions within the motor sector of the nervous system. These malfunctions, which are caused either by the surplus (as in HD) or absence (as in PD) of hormones, are a direct result of neural cell deterioration within the brain. PD and HD illustrate two very different behavioral patterns that are subsequently caused by two opposite and extreme biological abnormalities. Yet the common thread between the two conditions is that there are major mechanical predicaments arising between cellular connections within the brain.

The discovery from the Scripps Research Institute in Florida shows promising results in tackling down the cause of Parkinson’s, and their outcomes led to a funding by the National Institutional Disorders and Stroke Research (NINDS). Research staff within the campus discovers that many diseases that relate in twisting a protein from its original structure will result in a cellular death but it isn’t due to the deformed shape. According to the article “Scripps Florida Scientists' 'Mad Cow' Discovery” (2015), one primal cause that leads to Parkinson’s is the lack of “NAD+” which later prohibits the proper energy function of the mitochondria. Researchers further delved into the study to find out this is preventable, by providing the misshaped protein

Huntington 's Disease (HD) is a progressive brain disorder caused by a defective gene. This disease causes changes in the central area of the brain, which affect movement, mood and thinking skills. Nerve cells become impaired, causing several segments of the brain to fail. The disease disturbs movement, behavior and perception the affected people abilities to walk, think, reason and talk are slowly weakened to a point that they eventually become entirely dependent on other people for care. HD is a disease that affects the brain in many different ways. One of the ways the HD affects the brain is that it causes the person who has it to become forgetful and moody. Huntington 's disease also causes a decline in thinking and reasoning skills, including memory, concentration, judgment and ability to plan and organize.

The specific function of this protein is unknown, but researchers have discovered roles in several processes, which include the transportation of copper into cells and protect brain cells from injuries. Studies have shown a role for PrP in the form of synapsis, which is the junction in between neurons where communication of cell-to-cell occurs. HDL1 has been identified as the type of mutation in PRNP which causes the signs and symptoms of HDL Syndrome. The PRNP mutation involves a segment of DNA called an octapeptide repeat that provides the instructions to make eight amino acids that form to make a fragment called a peptide. The octapeptide typically repeats five times in PRNP. For the people who have HDL1, the segment repeats eleven to thirteen times. The increase in size of the octapeptide leads to abnormally long version of PrP. It’s not clear how the abnormal protein destroys and damages neurons, which is why it leads to the features of HDL1 (Huntington disease-like

Huntington disease is defined by the autosomal pattern that is in inheritance with high penetrance of high proportion of the population that has the gene that advances the disease. It’s typical that Huntington disease is caused by the loss of neurons nerve cells in the brain (Van Walsem M.R, 2016).

To this day, I have yet to meet another person with Huntington disease but I since then I have been intrigued by the disorder. The goal of this paper is to provide

3). In this gene, there is an expansion of CAG, or cytosine-adenine-guanine, which gives rise to an abnormal protein that modifies and damages cells in the brain (Roos, 2010, p. 1). The gene for the disease is dominant, which means that children of those with Huntington’s Disease have a 50% risk of acquiring the disease, with no regard to sex of the individual. This disease was probably discovered by Charles Waters, but named after George Huntington, who provided a better description, in 1872 (Roos, 2010, p.

Huntington’s disease occurs from acquiring a defective gene IT15 found on chromosome four. A typical copy of this gene yields the protein huntingtin. However, when the defective gene is bigger than usual, it yields huntingtin in a larger quantity. The etiology becomes fickle when reasons concerning why this defective protein damages the portion of the brain that administers movement. Scientists reveal that the reasoning is due to a miniscule protein called Rhes, which is found in the brain portion that governs movement. Overall, the mutant protein huntingtin causes Huntington’s disease and the defective protein Rhes contributes, however more research and testing is needed to explicate how the Rhes protein augments the pathology. The pathology entails progressive degeneration of the spiny neurons within the basal ganglia, chiefly the putamen and caudate. As the disease advances, neuronal loss ensues in the

Huntington’s disease is a hereditary brain disorder that affects people all over the world. If your parent has this disease, there is a fifty-percent chance that you will develop it at some point in your life. Huntington’s disease is caused by a defect in the dominate gene called huntingtin. This defect is caused by a part of DNA called CAG repeat. Normally the huntingtin gene is repeated about ten to twenty-eight times, and plays a major role in brain development. When a person has Huntington’s disease the huntingtin disease repeats anywhere from 36 to 120 times. When the gene repeats this much the elongated proteins separate into smaller pieces and collect neutrons, disrupting the normal cell function. This effects the parts of the brain

The HTT gene plays an important role in the brain’s nerve cells and involves a DNA segment known as CAG trinucleotide repeat. The CAG repeat is made up of a series of three DNA building blocks that appear multiple times in a row. A normal repeat of CAG is only 10-35 times within the gene, however, affected individuals have a 36-120+ repeat. An increase in the CAG size leads to the production of abnormally long versions the the Huntington Protein. These longer versions are then cut into smaller and toxic fragments that bind together and accumulate in neurons; this disrupts the normal functions of these cells. The dysfunctional, and eventual death, of neurons in specific areas of the brain control the signs and symptoms of Huntington Disease

The pathology of Huntington’s is a progressive, fatal, neurodegenerative disorder that is the result of an inherited autosomal dominant trait. Huntington’s is caused by an expanded huntingtin (HTT) gene that is located in the arm of chromosome 4, that encodes an abnormally long polyglutamine repeat protein. This mutation that was found about 20 years ago, we still do not have further knowledge on the mechanism in which the abnormally long polyglutamine repeat in the HTT protein worsens the nerve cells in specific brain region. Researchers find it challenging since the HTT protein prevails in all parts of the brain. Though, understanding the genetics of HTT helped investigators develop animal and cellular models to gain a closer look at the pathogenesis of Huntington’s. This investigation has led to the knowledge that mutated HTT is toxic to striated neurons, and that is related to some of the hundred proteins that networks with HTT. Though, as much of a help as animal and cellular models are, it will still not be sufficient enough to reveal an effective treatment. The conclusion from the animal and cellular models is that they need to be validated by examining and running tests on human autopsy tissues from prior Huntington’s patients, as well as controlled subjects.