Huntington’s disease (HD)

What is Huntington’s disease?

Huntington’s disease (HD) is a rare, inherited condition that affects the brain and nervous system. Over time, nerve cells in the brain break down and die, resulting in uncontrolled movements. HD is sometimes called Huntington’s chorea. Chorea is the medical term for the sudden, unpredictable, jerky movements that happen with this movement disorder.

Penn Medicine’s Movement Disorders Center is Huntington’s Disease Society of America (HSDA) Center of Excellence. This recognition is given to centers that use a collaborative, team-based approach to care. Our movement disorders care experts partner with you and your family to provide ongoing monitoring and support at every stage of care.

How Huntington’s disease affects the body

The first Huntington’s disease symptom to appear is typically chorea. These involuntary movements usually affect the hands and face first, followed by the limbs and torso. As the disease progresses, chorea can significantly impact the ability to drive, eat, speak, walk, and perform daily self-care.

All symptoms of HD are progressive, meaning that they get worse over time. Other symptoms include:

  • Difficulty speaking or swallowing
  • Changes in mood or personality, like irritability or depression
  • Seeing or hearing things that aren't there (hallucinations)
  • Stiff muscles and trouble with balance
  • Problems with balance and posture
  • Memory loss or trouble focusing on tasks

Why Huntington’s disease happens

Huntington’s disease is caused by a genetic variant of the HTT gene that is passed down through families. Only one parent needs to carry the abnormal gene to pass it down to a child. Each child born of that parent has a 50 percent chance of inheriting the condition.

In very rare cases, some people with HD do not have parents with the condition.

How Huntington’s disease is diagnosed

A family history of Huntington’s disease is often the strongest clue for diagnosis. A neurologist will review your personal and family medical history and perform a detailed physical and neurological exam. Your care team may also recommend genetic testing, even before symptoms appear, especially for people with a known family history. Genetic counselors help explain testing options, possible results, and what they may mean for you and your family.

Managing Huntington's disease symptoms

There is no cure for HD, but treatments may lessen symptoms and help manage disease progression.

Related specialties

Schedule an appointment

We can help you schedule an appointment or you can search our directory of specialists.