what is the genetic mutation of huntington's disease
Huntington's disease HD is typically inherited from a person's parents, although up to 10% of cases are due to a new mutation.[1] The disease is caused by an autosomal dominant mutation in either of an individual's two copies of a gene called Huntingtin.[4] This means a child of an affected person typically has a 50% chance of inheriting the disease.[4] The Huntingtin gene provides the genetic information for a protein that is also called "huntingtin".[1] Expansion of CAG (cytosine-adenine-guanine) triplet repeats in the gene coding for the Huntingtin protein results in an abnormal protein, which gradually damages cells in the brain, through mechanisms that are not fully understood.[4] Diagnosis is by genetic testing, which can be carried out at any time, regardless of whether or not symptoms are present.[5] This fact raises several ethical debates: the age at which an individual is considered mature enough to choose testing; whether parents have the right to have their children tested; and managing confidentiality and disclosure of test results.[2]
Huntington's disease Life expectancy in HD is generally around 20Â years following the onset of visible symptoms.[17] Most life-threatening complications result from muscle coordination and, to a lesser extent, behavioral changes induced by declining cognitive function. The largest risk is pneumonia, which causes death in one third of those with HD. As the ability to synchronize movements deteriorates, difficulty clearing the lungs and an increased risk of aspirating food or drink both increase the risk of contracting pneumonia. The second greatest risk is heart disease, which causes almost a quarter of fatalities of those with HD.[17] Suicide is the third greatest cause of fatalities, with 7.3% of those with HD taking their own lives and up to 27% attempting to do so. It is unclear to what extent suicidal thoughts are influenced by behavioral symptoms, as they signify sufferers' desires to avoid the later stages of the disease.[84][85][86] Other associated risks include choking, physical injury from falls, and malnutrition.[17]
My Ántonia
Alonso Álvarez de Pineda