Huntington’s disease

GENERAL ASPECTS

What is Huntington’s disease?

Huntington’s disease (HD) is an inherited, progressive, neurodegenerative disorder characterized by involuntary movements, psychiatric problems and dementia. It is a progressive disease, meaning that symptoms worsen over time.

Epidemiology

The estimated prevalence of HD is 5 to 8 per 100,000 people in Europe and North America. In other ethnic groups, the prevalence is lower.

What is the cause?

This disease is caused by a mutation in the Huntingtin gene (HTT) that leads to an expansion of a three-base sequence in the DNA, called CAG. This mutation causes damage and degeneration of nerve cells in the brain.

What are the symptoms of Huntington’s disease?

Symptoms usually begin gradually and may include:

• Involuntary movements: called chorea, which consist of irregular and involuntary movements that may be fast or slow and seem to flow from one part of the body to another, resembling a dance.
• Psychiatric problems: irritability, depression, anxiety, delusions, and other mood changes.
• Cognitive problems: difficulties with thinking and decision making.

As the disease progresses, movement problems worsen and may develop into stiffness and difficulty moving. Cognitive and motor function slowly deteriorates, affecting quality of life.

How is Huntington’s disease diagnosed?

Diagnosis is based on the presence of characteristic symptoms, a family history of the disease and genetic testing confirming the mutation in the HTT gene. In up to 8% the disease may be present without a clear family history, and some patients with typical symptoms may not show the mutation on testing.

Who should have genetic testing?

Genetic testing is recommended for:

• Adult patients with clear symptoms of the disease.
• Children with a positive family history and symptoms consistent with the juvenile form of the disease.
• Asymptomatic persons with a family history of Huntington’s disease, to know if they are at risk of developing the disease in the future.

What else do I need to know?

It is important to differentiate Huntington’s disease from other disorders that also cause involuntary movements. There are other inherited and acquired diseases that may have similar symptoms.

Recommendations:

1. Medical consultation: If you have symptoms of Huntington’s disease or a family history of the disease, seek guidance from a specialized physician.
2. Genetic testing: Talk to your doctor about the need for genetic testing if you are at risk or have symptoms.
3. Support and treatment: Huntington’s disease has no cure, but treatments are available to help manage symptoms and improve quality of life. A medical team can offer support in managing symptoms and planning for the future.