Parkinson’s and Huntington’s are both degenerative diseases that affect the brain. While they share some symptoms, they have distinct causes and tend to affect different populations.

Parkinson’s and Huntington’s disease are both neurodegenerative diseases that progressively affect the central nervous system (CNS). These conditions occur when nerve cells in the CNS deteriorate and die over time.

While they share some similarities in their effect on movement, there are distinct differences between them. Parkinson’s occurs when there’s a loss of dopamine-producing cells in the brain. Huntington’s is a genetic disorder.

Read on to learn more about the similarities and differences between Parkinson’s and Huntington’s disease, including their causes, symptoms, possible treatment options, and outlooks.

Parkinson’s disease is a progressive nervous system disorder that gradually affects movement.

Parkinson’s results from the loss of dopamine-producing cells in the brain. This leads to decreased dopamine, a chemical that helps control movement and coordination.

While the exact cause of Parkinson’s is unknown, experts believe a combination of genetic and environmental factors may increase the risk.

Huntington’s disease is a rare genetic disorder that causes neurodegeneration of the brain. It results from a mutation in the Huntingtin (HTT) gene involving excessive cytosine-adenine-guanine (CAG) repeats.

These repeats in the genetic code result in the production of a mutant protein that accumulates in brain cells, leading to their death.

Role of basal ganglia in Parkinson’s and Huntington’s

The basal ganglia is a collection of brain structures that help with motor control and coordination.

Parkinson’s disease primarily affects the substantia nigra, a part of the basal ganglia, leading to decreased dopamine production. This affects the balance between dopamine and acetylcholine, a neurotransmitter involved in movement, which causes movement difficulties.

Huntington’s disease directly affects the basal ganglia. It most notably affects the striatum, which includes the caudate and putamen. The striatum plays a role in motor control, emotion, and reasoning.

Parkinson’s and Huntington’s are both neurodegenerative disorders that affect the CNS, but they have distinct symptoms.

In Parkinson’s disease, the primary symptoms are motor-related, such as:

On the other hand, Huntington’s disease symptoms relate to involuntary movements, such as:

  • involuntary jerking movements (chorea)
  • muscle contractions causing abnormal postures (dystonia)
  • sudden, brief muscle twitches (myoclonus)

Changes in thinking ability are a main feature of Huntington’s. It also frequently causes psychiatric symptoms, such as depression, anxiety, and psychosis.

At what age do symptoms of Parkinson’s and Huntington’s appear?

Parkinson’s symptoms typically appear in adults over age 60 years, though they can develop earlier.

In contrast, symptoms of Huntington’s disease typically start between 30 and 50 years old.

Huntington’s is a genetic disease, so doctors can confirm a diagnosis with a blood test. Because of this, it’s not common for doctors to misdiagnose other conditions as Huntington’s disease.

But if doctors do not suspect Huntington’s disease, they may misdiagnose it as something else, especially in cases where it develops later in life.

Although Parkinson’s and Huntington’s may have some overlapping symptoms, an experienced neurologist can typically distinguish between the two.

People with Huntington’s, especially older adults, may display symptoms of parkinsonism, such as decreased facial expression and stooped posture.

Consider talking with a qualified healthcare professional for a proper evaluation and diagnosis to differentiate between Parkinson’s and Huntington’s disease accurately.

Parkinson’s treatment primarily focuses on managing symptoms and improving dopamine levels in the brain. Medications that can enhance dopamine function and reduce motor symptoms include:

Other treatment options for Parkinson’s include:

The main goal of Huntington’s treatment is to manage motor and nonmotor symptoms. A healthcare professional may prescribe or recommend:

  • tetrabenazine (Xenazine) to manage chorea
  • antipsychotics, mood stabilizers, and antidepressants to help with psychiatric symptoms
  • speech, occupational, or physical therapy to improve overall quality of life

While Parkinson’s disease is a chronic condition, its progression and severity can vary among people. With appropriate treatment and management, you may slow its progression and maintain a good quality of life.

Huntington’s disease has no cure and tends to progress for 15–20 years. It leads to a decline in motor and cognitive function, which can result in disability and a need for caregivers.

Compared with those who have Parkinson’s, people with Huntington’s have a shorter life expectancy, living into their 60s, on average.

How does Alzheimer’s differ from Parkinson’s and Huntington’s?

Parkinson’s and Huntington’s involve motor and cognitive symptoms. Huntington’s also causes psychiatric symptoms.

Alzheimer’s disease is a different neurodegenerative disease. It primarily affects memory and cognitive function. It often appears as progressive memory loss, confusion, and difficulty with problem-solving and language.

Although these diseases share some similar characteristics, they differ in their primary symptoms, progression, and underlying causes.

Some frequently asked questions about Parkinson’s and Huntington’s disease include:

Which is more common: Parkinson’s or Huntington’s?

Parkinson’s disease is more common than Huntington’s disease. Parkinson’s is the second-most common neurodegenerative disease (after Alzheimer’s), affecting more than 10 million people globally, according to the Parkinson’s Foundation.

Huntington’s disease is rare, affecting 2.7 per 100,000 people worldwide.

Can you prevent Parkinson’s or Huntington’s disease?

Because Huntington’s is a genetic disease, you cannot prevent it. People born with an HTT gene mutation that causes 40 or more CAG repeats are predestined to develop Huntington’s.

There’s also no proven way to prevent Parkinson’s disease, but some experts think that modifying environmental and lifestyle factors, like diet and exercise, may help reduce risk.

Experts think that both conditions may have a genetic component. Research has linked about 20 genes to Parkinson’s disease.

What other conditions can mimic Parkinson’s or Huntington’s?

Several diseases that affect motor control may mimic Parkinson’s. These include essential tremors and progressive supranuclear palsy.

The psychiatric symptoms of Huntington’s disease sometimes lead healthcare professionals to misdiagnose it as schizophrenia. Other mimics of Huntington’s disease include tardive dyskinesia and Wilson disease.

Parkinson’s disease and Huntington’s disease are neurodegenerative conditions affecting the brain. While they share some similarities, each condition has distinct symptoms and requires different treatment approaches.

While both can cause issues with movement, Huntington’s is an inherited condition with symptoms that tend to start in middle adulthood. You may also experience psychiatric symptoms with Huntington’s.

Consider speaking with a doctor for accurate diagnosis and management.