Huntington's disease

Huntington's disease (also known as Huntington's chorea) is a hereditary disease that is marked by chronic, progressive chorea and marked mental deterioration in middle life, usually in the fourth decade.

The disease has a prevalence of about 1 in 20,000 in the UK. It is inherited as an autosomal dominant trait with full penetrance (meaning that individuals born to a parent with Huntington disease have a 50% chance of developing the disease). The family history of the disease is often concealed.

The gene responsible for this condition resides on chromosome 4. Predictive DNA testing of at risk relatives of sufferers reduces anxiety, whatever the test outcome.

Symptoms of Huntington disease typically first appear between ages 30 and 50 years and include

• motor function disturbances: including involuntary, jerking or writhing, dance-like movements (chorea) of the face, torso, and limbs; involuntary muscle contractions (dystonia); impaired eye movements; and slurred speech
• cognitive disturbabces: including disturbances in planning, processing speed, memory, and judgment
• mood disturbances: including depression, anxiety, apathy, agitation, and psychosis

Reference:

• Marcus R. What Is Huntington Disease? JAMA. 2023;330(10):1014. doi:10.1001/jama.2023.13024