Apart from this broad similarity, HD and ALS are separate conditions.
Huntington’s diseaseis an inherited condition associated with uncontrolled movements, psychiatric disturbances, and cognitive decline.
The vast majority of ALS cases are not inherited.
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Symptoms are motor (movement-related), cognitive, and psychiatric.
The weakness of ALS classically begins in an arm or leg before spreading throughout the entire body.
Over time, people lose their ability to dress, bathe, walk, eat, and breathe independently.
Causes
A critical difference between Huntington’s disease and ALS is its cause.
Huntington’s disease is because of a genetic abnormality, whereas the cause of ALS is largely unknown.
What Causes Huntington’s Disease?
Huntington’s disease is anautosomaldominant disorder.
What Causes ALS?
Unlike Huntington’s, ALS does not usually run in families, although there is a genetic component.
Over 50 genes are identified as being linked to ALS.
Interestingly, many of these genes are involved in RNA metabolism.
RNA is a molecule within living cells that creates proteins using cells' genetic information.
Besides genetics, various environmental factors may increase a person’s chances of developing ALS.
For ALS, the diagnosis requires a bit more detective work.
A genetic blood test that checks for the presence of the HTT mutation can then confirm the diagnosis.
The HTT gene mutation is found onchromosome4 and is associated with increased CAG repeats.
What Is CAG?
“CAG” stands for the nucleic acids cytosine, adenine, and guanine.
These are molecules in DNA that code for proteins.
Huntington’s disease develops when increased CAG repeats are present.
Usually, people have less than 26 CAG repeats.
Various tests will be ordered to help confirm the diagnosis.
Treatments generally focus on managing specific symptoms, preventing complications, and maintaining comfort and quality of life.
If you have suicidal thoughts, dial988to reach the988 Suicide & Crisis Lifelineand connect with a trained crisis worker.
Call911or go to your nearest emergency room if you are in immediate danger.
ALS Treatment
As with Huntington’s disease, therapies for ALS are primarily supportive.
These drugs are intended to slow the disease down and, possibly, prolong survival.
If the gene is not present, they will not transmit the condition to their children.
Huntington’s disease is inherited, resulting from a faulty gene that can be passed down from a parent.
The disease affects the body and mind, causing uncontrolled movements and psychiatric and cognitive problems.
ALS primarily affects the muscles causing progressive weakness and eventual paralysis.
With ALS, the cause remains unknown in most cases.
Of note, there are three FDA-approved drugs intended to help slow ALS down.
No such drugs exist yet for Huntington’s disease.
You might exhibit anxiety, despair, anger, or even emotional numbness.
These feelings can ebb and flow as you navigate the various challenges of living with such a disease.
While being diagnosed with HD or ALS is distressing, know that you are not alone.
Frequently Asked Questions
Huntington’s disease and ALS are associated with motor (movement-related) symptoms.
The hallmark motor symptom of Huntington’s disease is uncontrollable movements (chorea).
For ALS, the hallmark symptom is widespread muscle weakness.
There is no cure for either condition.
Treatment focuses on easing symptoms and maintaining the quality of life.
Currently, there are three FDA-approved ALS drugs intended to slow disease progression.
There are no treatments that can help slow the progression of Huntington’s disease.
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