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's 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 disturbances: including disturbances in planning, processing speed, memory, and judgment
• mood disturbances: including depression, anxiety, apathy, agitation, and psychosis

Reference:

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