Huntington's Disease Etiology

Etiology Huntington’s Disease is an inherited disease. The gene mutation is found on chromosome four (Johns Hopkins). This gene has a specific sequence that is repeated an abnormally large number of times (Johns Hopkins). The more repeats of the sequence, the more likely it is that a person will develop Huntington’s Disease earlier in their lifetime (Johns Hopkins). For most people, the sequence is repeated ten to thirty-five times in one gene, but for people with Huntington’s Disease, the sequence is repeated thirty-six to 120 times in one gene (U.S. National Library of Medicine, 2013). People who have the sequence repeated thirty-six to thirty-nine times may or may not develop the disease, but people who have the sequence repeated forty
or more times, will always develop the disease (U.S. National Library of Medicine, 2013). It is an autosomal dominant disease (Johns Hopkins).
The protein that is misfolded is called huntingtin; its exact function is unclear, but it is believed to be incredibly important to the sustainability of neurons of the brain (U.S. National Library of Medicine, 2013). Every child born to a parent with this gene had a 50 percent chance of inheriting the disease (Mayo Clinic, 2014). This also means that if a child born to someone who suffers from Huntington’s Disease does not suffer from the disease themselves, they are a carrier and can pass it to their children (Johns Hopkins). If the child inherits the disease form their father, instead of their mother, it is more likely that the disease will begin earlier in the child’s lifetime; this is called anticipation (Johns Hopkins).