Huntington's Disease – Mayo Clinic

Every cell within the body contains this entire set of chromosomes, which have bases arranged to form a code (Appai-Kubi). The four bases, cytosine, adenine, guanine, and thymine, interact to form the fundamental structure of DNA (Appai-Kubi). Huntington’s Disease is found on the fourth chromosome, with a sequence known as the “CAG repeat,” (Appai-Kubi). In someone who is not afflicted, the number of CAG repeats ranges from 10 to 28 (Sheth). Typically, more than 35 repetitions of CAG is associated with Huntington’s Disease, however, there are cases with people having up to 39 repeats not having the disease (Appai-Kubi). As the gene is passed on through families, the number of repeats generally increases, and with an increased number of CAG repeats, the earlier the symptoms develop (Sheth). This characteristic of the disease allows it to be tested for, by testing the frequency of CAG on chromosome 4 (Appai-Kubi.) During pregnancy, a woman can test for Huntington’s Disease in two ways; either amniocentesis, taking fluid from around the fetus, or by CVS, taking a sample of fetal cells from the placenta (Genetic Learning Center). A genetic test after birth can confirm the diagnosis after a series of neurological and psychological tests (Genetic Learning Center). Huntington’s Disease is inherited through an autosomal dominant pattern; meaning that whoever inherits the faulty gene will develop the disease throughout their lifetime (Genetic Science Learning

In 1993 it was discovered that a segment of DNA on the arm of chromosome 4 is linked to the HD gene. They found that at one end of the HD gene, the combination CAG is repeated too many times. In people without HD this CAG is repeated 5 to 35 times. In people who are affected by HD, CAG is repeated over and over again between 36 and 121 times.

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

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.

Everyone can relate to the pain of having to watch a grandparent or great-grandparent slowly loose their faculties as they advance into older age. Now, imagine if this seemingly slow digression hit hard and fast at only age thirty. The age where one is finally living alone and independent, with the beginnings of a successful career and the hopes of starting a family and settling down. Huntington’s Disease quickly takes all these dreams and ambitions away, along with control of ones body and mind. The symptoms of Huntington’s, such as involuntary muscle jerks or twitches, had been seen throughout history for many years before being first recognized as an inherited disease in 1872 by Dr. George Huntington (“Hope Through Research). “The hereditary

Huntington's disease is characterized by atrophy of the caudate nucleus and putamen. There are two populations of GABAergic striatal efferent neurons that are involved and this is evident based on their projection targets and neuropeptide content. In the very early stages of the disease there is a major loss of

For our gene and protein lab, my group decided and I to research the deadly, yet rare, disease, known as Huntington's disease. Huntington's disease is an extremely rare condition when your nerve cells in your brain break down overtime. Also, “HD” has a treatment that could aid someone, but it unfortunately cannot be cured. Huntington’s Disease typically begins when someone is thirty or forty years of age and can last years to a life time.

Rooting back to the middle ages the now commonly known Huntington’s disease is the cause of death in one out of 15000 people around the globe. The disease’s existence is documented through history under many different names depending on the amount of information that was gathered through the unusual progression of the disease. The disease was referred to as Chorea initially due to the jerky movements of the patients affected by it. The first thorough description of the disease surfaced in 1872 as George Huntington whom the disease is named after today presented a detailed definition of the disease through his first paper. George Huntington was able to accurately detect the pattern of inheritance of an autosomal dominant disease by examining the combined medical histories of a family that clearly suffered from the disease through generations. The disease could not be studied further until the rediscovery of the Mendelian Inheritance in the 20th century that allowed scientist to look further into the autosomal dominant disease.

Huntington’s disease is caused by the mispelling in the HTT gene for a huntingtin protein. Involved in the HTT mutation that causes Hungtington’s disease, the CAG trinucleotide

Huntington disease is a destructive brain disorder for which there are currently no cure. Some medications have been proven to ease symptoms of the disease including Tetrabenazine which is a medication which helps conceal the uncontrollable jerking and writhing movements. The most promising approach to curing Huntington disease is developing drugs that would tell our cells to make less of the damaging Huntington protein. Scientist are on the verge of using gene therapy to correct the mistakes in our DNA causing Huntington disease.

However, anyone with 36 to 39 repeats are at risk for developing Huntington’s disease, while those with 40 or more is highly probable for developing the disorder. As the mutated HTT gene is passed down from generation, the CAG trinucleotide repeat is lengthened. Generally, the longer the repeated sequence, the earlier the onset of the disorder. Patients with 40 to 50 repeats generally will have an adult onset while those with 60 or more will have a juvenile version. Individuals with 27 to 35 repeats are at risk of having children with the disorder, despite not having them disease themselves

The symptomotology of Huntington’s have been recognized for several hundreds of years, but the etiology was ambiguous until recently when it was discovered that an expansion in the polyglutamine tract led to misfolding (citation). Although a lot of progress has been made, the way in which the mutant Huntingtin protein damages cells is still not fully understood. The events that preceede the discovery were crucial and are a perfect example of the use of pedigrees and linkage analysis to identify the locus of the causal gene of a disease.

Huntington’s disease (HD) is a rare and fatal disease known as a polyglutamine neurodegenerative disorder effecting only 4-10 per 100,000 people of European decent (Driver-Dunckly et. Al 2007). This means there is a problem with the trinucleotide that codes for glutamine, cytosine-adenine-guanine (CAG). In the case of HD there is an extreme overproduction of the CAG repeats in the protein huntingtin. Accumulation of this mutated form of the protein in neurons causes cell atrophy which in turn causes the brain to malfunction. The disease was first described by Dr. George Huntington in 1872, however it wasn’t until 1993 that the cause of the disease was actually discovered (Bertram et. Al 2005).HD is characterized by symptoms effecting the afflicted

The huntingtins gene allele expands greater than 36 CAG units. But the normal individuals have less than 36 CAG units. Huntingtin is the names for the defective protein that the mutation generates. The protein has uncertain molecular function that makes it found throughout the body (Barboza and Ghisi 2018). This explains the disorder that causes Huntington disease and describe what the normal protein unit would look in a person who doesn’t have Huntington disease versus a person whom is a potential carrier of the disease. Studies by Barboza and Ghisi reveal Huntingtin causes changes in both the neostriatum and cerebral cortex. The disease development is a result in a loss of the Huntington’s gene (Barboza and Ghisi (2018). The mutant causes changes in the neostriatum and cerebral cortex which explains how the mutant affects the body and how the disease is developed. An earlier report by Barboza and Ghisi reveal If the parent has Huntington’s disease it gives the parent a 50% chance of passing it to their children. Which means it’s a dominant disease. The mutation increases every generation and completely ignores mendelian inheritances because of the repeated trinucleotides. (Barboza and Ghisi 2018). This describe what mutation can lead do and how mutations

Researchers looked the chromosomes of more than 4,000 Huntington's malady patients and found that DNA repair qualities may focus when the neurological manifestations start. Incompletely subsidized by the National Institutes of Health, the outcomes may give a manual for finding new medications for Huntington's ailment and a guide for examining other neurological issue. Huntington's disease is an acquired neurodegenerative issue brought on by transformations in a quality that encodes a protein called Huntingtin. Indications of the disease normally start in your midlife and incorporate uncontrolled developments, enthusiastic aggravations and, in the long run, dementia. Despite the fact that studies in people and creatures have found pieces of