Hush puppy

Huntington's disease (HD), also known as Huntington's chorea, is a neurodegenerative genetic disorder that affects muscle coordination and leads to cognitive decline and psychiatric problems. It typically becomes noticeable in mid-adult life, with symptoms often beginning between 30 and 50 years of age.

Causes

HD 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.

Symptoms

The earliest symptoms are often subtle problems with mood or mental abilities. A general lack of coordination and an unsteady gait often follow. As the disease advances, uncoordinated, jerky body movements become more apparent, along with a decline in mental abilities and the physical health of the person. Physical abilities gradually worsen until coordinated movement becomes difficult. Mental abilities generally decline into dementia.

Diagnosis

The diagnosis of HD is based on the symptoms and signs in a person after a family history has been considered. Genetic testing can be used to confirm a physical diagnosis if there is no family history. However, genetic testing does not predict when symptoms will begin.

Treatment

There is no cure for HD. Full-time care is required in the later stages of the disease. Existing pharmaceutical and psychiatric treatments can help manage the symptoms, but do not slow the physical, mental and behavioral decline.

Research

Research directions on HD include determining the exact mechanism of the disease, improving animal models to aid with research, testing of drug treatments, and studying potential gene therapy interventions.