Huntington's Disease

Huntington's Disease (HD) is a neurological disorder that impairs voluntary movement and cognition. Adult onset of the disease is usually in the 30s and 40s, but HD can occur in juveniles. Juvenile HD patients usually die 10 to 15 years after their symptoms appear.

Huntington's Disease causes changes in mood, impaired cognition, and motor symptoms (such as chorea, small involuntary movements). Huntington's disease affects the basal ganglia and the cerebral cortex.

Huntington's disease can be traced to genetics. It is caused by a dominant inheritance for a mutation of the huntingtin (HTT) gene located on chromosome 4, which codes for the huntingtin protein. The mutation involves an abnormal amount of repeats for a three-part snippet of DNA. Normally, people have 10 to 35 repeats of the sequence CAG (cytosine, adenine, guanine). HD patients, however, can have 36 to 120 of these repeats, known as a trinucleotide repeat.

Potential HD biomarkers are tau (also found in Alzheimer's) and neurofilament light chain.

Treatments include deutetrabenazine, an FDA-approved treatment for chorea associated with HD. The IONIS-HTTRx drug is in a trial phase that is designed to silence the mutated HTT gene.

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Image Credit:
(1) NIST. “Huntington's Disease.” Wikimedia Commons, 12 Apr. 2011, upload.wikimedia.org/wikipedia/commons/d/d5/Huntington%27s_disease_%285880985560%29.jpg.

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