Overview
Juvenile Huntington disease (JHD), also known as Westphal variant of Huntington disease, is a rare form of Huntington disease (HD) that manifests before the age of 20 years. It is caused by an expanded CAG trinucleotide repeat (typically ≥60 repeats) in the HTT gene on chromosome 4p16.3, which encodes the huntingtin protein. JHD accounts for approximately 5–10% of all Huntington disease cases. The disease primarily affects the central nervous system, leading to progressive neurodegeneration of the basal ganglia (particularly the caudate nucleus and putamen) and cerebral cortex. Unlike adult-onset HD, juvenile Huntington disease more commonly presents with rigidity, bradykinesia (slowness of movement), dystonia, and cerebellar signs rather than the classic chorea seen in adults. Seizures occur in a significant proportion of patients, particularly those with childhood onset. Cognitive decline is prominent and often manifests as deteriorating school performance, behavioral changes, and progressive dementia. Oral motor dysfunction leads to dysarthria and dysphagia. Psychiatric symptoms including depression, irritability, aggression, and apathy are frequently observed. The disease follows a more rapid and severe course than adult-onset HD, with an average disease duration of approximately 10–15 years from symptom onset. JHD is most often inherited from an affected father due to the tendency for CAG repeat expansion during paternal transmission (anticipation). There is currently no cure or disease-modifying treatment for juvenile Huntington disease. Management is symptomatic and supportive, including antiepileptic medications for seizures, pharmacotherapy for psychiatric symptoms and movement disorders (such as benzodiazepines or baclofen for dystonia and rigidity), speech and physical therapy, nutritional support, and multidisciplinary care. Several investigational therapies targeting the huntingtin protein are under study, but none have yet demonstrated efficacy in clinical trials.
Also known as:
Clinical phenotype terms— hover any for plain English:
Autosomal dominant
Passed on from just one parent; each child has about a 50% chance of inheriting it
Juvenile
Begins in the teen years
FDA & Trial Timeline
1 eventUniversity of Iowa — NA
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
No FDA-approved treatments are currently listed for Juvenile Huntington disease.
1 clinical trialare actively recruiting — trials can provide access to cutting-edge therapies.
View clinical trials →Rare Disease Specialist
Treatment Centers
8 centersVanderbilt University Medical Center
📍 Nashville, Tennessee
Columbia University Medical Center
📍 New York, New York
👤 Janssen Research & Development, LLC Clinical Trial
👤 Anthony A. Amato, MD
Stanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
Travel Grants
No travel grants are currently matched to Juvenile Huntington disease.
Community
No community posts yet. Be the first to share your experience with Juvenile Huntington disease.
Start the conversation →Latest news about Juvenile Huntington disease
Disease timeline:
New trial: Longitudinal Assessment of Brain Structure and Function in Juvenile-onset Huntington's Disease
Phase NA trial recruiting.
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Common questions about Juvenile Huntington disease
What is Juvenile Huntington disease?
Juvenile Huntington disease (JHD), also known as Westphal variant of Huntington disease, is a rare form of Huntington disease (HD) that manifests before the age of 20 years. It is caused by an expanded CAG trinucleotide repeat (typically ≥60 repeats) in the HTT gene on chromosome 4p16.3, which encodes the huntingtin protein. JHD accounts for approximately 5–10% of all Huntington disease cases. The disease primarily affects the central nervous system, leading to progressive neurodegeneration of the basal ganglia (particularly the caudate nucleus and putamen) and cerebral cortex. Unlike adult-o
How is Juvenile Huntington disease inherited?
Juvenile Huntington disease follows a autosomal dominant inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.
At what age does Juvenile Huntington disease typically begin?
Typical onset of Juvenile Huntington disease is juvenile. Age of onset can vary across affected individuals.
Are there clinical trials for Juvenile Huntington disease?
Yes — 1 recruiting clinical trial is currently listed for Juvenile Huntington disease on UniteRare. See the clinical trials section on this page for phase, sponsor, and site details sourced from ClinicalTrials.gov.
Which specialists treat Juvenile Huntington disease?
4 specialists and care centers treating Juvenile Huntington disease are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.