RARE Hope (formerly Hope for Annabel)

Patient-Partnered Collaboration

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Alternating Hemiplegia of Childhood (AHC) is a neurological disorder caused by an ion imbalance in the brain that prevents the correct functioning of neurons.

Last updated 04/30/2026

Clinical

Disease Class

Neurological diseases

Body Systems

Cardiovascular / Circulatory

Nervous / Sensory

Organs

Brain

Heart

Known Genetic Link

Yes, one or more genes directly cause the condition

Causative Genes

ATP1A3

Contributory Genes

None specified / unknown

Type of Inheritance

De novo

Newborn Screening

Yes, for some genes

Disease Mechanism(s)

Unknown

Age of Onset

Early childhood (age 1+-5)

Infancy (age 0-1)

Average Age at Diagnosis

Early childhood (age 1+-5)

Infancy (age 0-1)

Life Expectancy

Adulthood (age 18-64)

Affected Sex(es)

Female

Male

National Prevalence

101-1000

Global Prevalence

1001-10000

National Incidence

Less than 10

Global Incidence

Less than 10

Symptoms / Phenotypes

autism

behavioral changes

cerebellar atrophy

developmental delay

hypotonia

movement disorders / ataxia / tremor

paralysis

seizures / epilepsy

Biomarkers

None

Existing Therapies

None

Therapies in Development

Antisense oligonucleotide (ASO) therapy

Gene therapy

· Gene supplementation

Other (please specify)

· Prime Editing/Base Editing

Repurposed drug

Therapeutic Development Stages

In preclinical development

In research/exploratory phase

Therapeutic Development Role

Access to registry or natural history study

Data sharing

Focus group participation or coordination

Funding

Meetings with regulators (e.g., FDA listening sessions, PFDD meetings)

Outcome measures development

Recruitment and outreach to patients

Recruitment and outreach to trial sites / physicians

Results dissemination (including publications)

Sample provision

Study material design and/or review (not protocol) — includes patient-facing materials such as informed consent

Study protocol design and/or review (includes selection of outcome measures)

Travel coordination

Organizational & Research

Cell Lines

iPSCs

Cell Lines, Institution

Northwestern University

Vanderbilt University

Cell Lines, Involvement

Consulted

Funded

Own

Cell Lines, share

Unsure

Disease Model

C. elegans

Mouse

Disease Model, Involvement

Funded

Disease Model, share

All our disease models are freely available

Clinical Trial Role

Not involved

Biobank, Institution

Massachusetts General Hospital

Biobank, Involvement

Consulted

Funded

Center of Excellence, Institution

Duke University

Center of Excellence, Involvement

Consulted

Endorsed/Certified/Accredited

Funded

Registry

Yes, we have a registry that we created

Data Collected, Registry

Patient contact info

Patient-reported data

Data Entered by, Registry

Patients

Platform, Registry

Not specified

Natural History Study

Yes, we have a natural history study that we created

Data Collected, Natural History Study

Electronic health records/electronic medical records

Genetic data

Patient-reported outcomes

Platform, Natural History Study

Not specified

FDA Patient Listening Session

FDA Patient-Focused Drug Development (PFDD) Program

ICD Codes

No, we do not have any ICD codes

Diagnostic Guidelines

Yes, we have guidance available on our website

Science Advisory Board Policies

Does not have an SAB

Research Network Policies

Has CRN but no policies

Patient Priority Survey

Yes

Patient Priority Survey, share

Yes, will share

Research Roadmap

Yes we have a Research Roadmap, but will not share policies

None

Europe

North America

None