Adult-onset Huntington's Disease, second Post
Huntington’s Disease is a genetic disorder that causes the progressive breakdown of nerve cells in the brain. It well known for causing uncontrolled movement, emotional problems, and loss of cognition. HD is caused by a mutation in the mhTT gene on chromosome 4. This gene gives instructions for making a protein called Huntingtin. The exact function of this protein is unclear, but it is believed that this protein is important to nerve cells in the brain. The mutation in the mhTT gene that leads to HD involves a DNA segment known as a CAG trinucleotide repeat. The CAG segment in a normal HTT gene repeats 10 to 35 times. In people with HD, it repeats from 36 to over 120 times. The excessive repetition of this DNA segment results in a larger form of the Huntingtin protein. HD is referred to as the quintessential family disease because every child of a parent with HD has a 50/50 chance of caring the faulty gene. This is because HD is inherited in an autosomal dominant manner. Theref