Question: what is the genetic mutation of huntington's disease

title: Huntington's disease
text: HD is typically inherited from a person 's parents , although up to 10 % of cases are due to a new mutation . The disease is caused by an autosomal dominant mutation in either of an individual 's two copies of a gene called Huntingtin . This means a child of an affected person typically has a 50 % chance of inheriting the disease . The Huntingtin gene provides the genetic information for a protein that is also called `` huntingtin '' . 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 . Diagnosis is by genetic testing , which can be carried out at any time , regardless of whether or not symptoms are present . 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 . 

Answer: answer: The disease is caused by an autosomal dominant mutation in either of an individual's two copies of a gene called Huntingtin.  The Huntingtin gene provides the genetic information for a protein that is also called `` huntingtin ''.  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.