Many different types of diseases have been discovered in science, some of these diseases have been linked to genetics. A specific genetic disease is Huntington's disease. Huntington's disease is a genetically linked disease caused by a dominant allele. Although Huntington's disease is genetic, there are underlying concepts as to how exactly Huntington's disease becomes genetically linked to an individual who acquires the disease. Huntington's disease is a genetic disorder that has been thought to be fatal due to the nature and side effects of the disease. The disease affects the motor, cognitive and physical abilities of every individual affected by the disease. The disease is considered a degenerative disease because the lack of motor, cognitive and physical abilities leads to dementia and/or depression. The disease is classified as a dominantly inherited neurodegenerative disease, caused by the expansion of the CAG trinucleotide in exon 1 of the Huntingtin (Bissonnette 1) gene. There are numerous numbers of CAG (glutamine) repeats in the huntingtin gene. Polyglutamine expansions lead to a variety of cellular abnormalities (Journal of Neuroscience). Chromosomes during fetal development are affected, chromosome four is the chromosome associated with the change in the Huntingtin gene. The Huntingtin gene can be passed on by both males and females. The Huntingtin gene is expanded on one of two chromosomes four. Both mom and dad can have an expanded chromosome four gene that would be passed on and appear dominant. If a parent is affected by one of the two chromosome fours that they are a carrier, this will be passed on to the child. About half of the eggs will contain the chromosome with the expanded H......in the center of the paper cells......and will cause an abundance of proteins in the nuclei of the cells. Usually the affected chromosome of those with Huntington's disease is chromosome number four. A higher number of CAG repeats worsens symptoms and increases the likelihood of developing Huntington's disease, the lower the number of repeats, the lower the likelihood of having symptoms and/or developing Huntington's disease. Although it is a devastating disease, is there ongoing research to try to slow the progression of this disease and/or reduce its development? Tests of mithramcyin treatment in mice have shed light on whether it can help individuals with Huntington's disease and whether it can slow the degeneration of brain function and/or loss of mobility. Hopefully in the near future Huntington's disease will be more under control and help people who suffer from it.