Huntington's Disease: The Huntingtin Gene

Huntington’s disease is inherited, meaning that an individual who has a parent with Huntington’s will have a fifty percent chance of inheriting the gene, which will in turn will eventually lead to the onset of the disease (Oster, Shoulson, & Dorsey, 2013). It is the neurodegeneration of the brain, but have more specifically been found in the basal ganglia and cerebral cortex (de Paula, Concalves, & Vieira, 2015). The huntingtin gene (HTT) is the instruction manual to produce the protein huntingtin, which helps neurons in the brain to function (Huntington disease, 2016).
The mutation is in the HTT gene in the DNA segment CAG trinucleotide repeat, which is repeated up to 120 times more than normal. However, people with less than 40 repeats may not ever have onset of the disease, but they have the ability to pass it on to their own children. When CAG repeats the segment increases in size creating a abnormally long protein, which accumulates in neurons after it is cut into pieces, and disturbs the neuron function (Huntington disease, 2016).
Since the genetic cause and aspect of Huntington’s disease has been discovered, genetic testing can be done with a blood test to determine if an individual has the mutation and will develop the disease or not.
There are low rates of genetic testing though, as only 5 to 10 percent of individuals who are at risk choose to partake in predictive testing. Low testing rates are due to the high costs, the amount of time that the testing process takes is long, and other individuals do not want to live their lives awaiting a future that will hold illness (Oster, Shoulson, & Dorsey,
2013).