About Alagille Syndrome
Alagille syndrome (ALGS) is an autosomal dominant multi-system disorder caused by mutations in the JAG1 or NOTCH2 genes, which regulate the Notch signaling pathway critical for normal organ development and tissue maintenance throughout life. The hallmark hepatic feature is intrahepatic bile duct hypoplasia, characterized by a decreased number of interlobular bile ducts with progressive obliteration of remaining ducts leading to cholestasis and progressive liver disease.
Cardiac involvement occurs in approximately 90% of patients, most commonly manifesting as pulmonary stenosis or other right-sided heart lesions. The characteristic facial features include a broad forehead, pointed chin, hypertelorism (widely-spaced eyes), and straight nose that become more apparent with age. Skeletal abnormalities including butterfly vertebrae and scoliosis are common and may cause functional limitations. Ocular abnormalities such as posterior embryotoxon and retinal pigmentary changes, along with hearing loss, occur in variable proportions.
Notably, disease severity varies dramatically among affected individuals: some patients maintain relatively normal liver function into adulthood with minimal symptoms, while others develop progressive cirrhosis with portal hypertension, esophageal varices, and liver failure requiring transplantation by late childhood. This remarkable variability in phenotype is even observed within families carrying the same mutation.
Common Symptoms of Alagille Syndrome
Recognizing the signs of Alagille Syndrome early can lead to faster diagnosis and better outcomes. Symptoms may vary in severity from person to person. If you or a loved one are experiencing any of the following, consider speaking with a specialist.
- Cholestasis and jaundice in infancy
- Bile duct hypoplasia and progressive liver disease
- Cardiac defects including pulmonary stenosis
- Characteristic facial features
- Skeletal abnormalities and butterfly vertebrae
- Hearing loss and eye abnormalities
Who Alagille Syndrome Affects
Alagille syndrome typically manifests in infancy with cholestasis presenting as jaundice and pale stools, though age of onset and severity vary considerably.
The condition affects males and females equally. Since it follows autosomal dominant inheritance, approximately 50% of children born to an affected parent inherit the condition. Both familial cases and de novo mutations occur. Expression is highly variable with incomplete penetrance, meaning some carriers of mutations have minimal or no clinical manifestations while others develop severe multisystem disease.
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Help Paying for Alagille Syndrome Treatment
Charity funds and drugmaker programs for Alagille Syndrome, checked at the source. Pick your insurance to see what fits.
- From a charity · Alagille Syndrome AllianceALGSAssistance Program fundOpen
Pays for: Rent or mortgage, utilities, insurance premiums, counseling, and medical, adaptive or mobility equipment, up to $1,000 per year.
The foundation says: “Apply now (reviewed case by case as funding allows)” - From a charity · HealthWell FoundationAlagille Syndrome Vitamins and Supplements fundOpen
Pays for: Copays, premiums or other treatment costs.
Side Effect Explorer
Real-world side effect reports from the FDA Adverse Event Reporting System (FAERS). Includes both FDA-approved drugs and investigational therapies from active clinical trials. Click any drug to see what patients reported.
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Genetic Testing
Genetic testing can confirm a diagnosis, guide treatment decisions, and identify family members who may be at risk.
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Trusted Alagille Syndrome Resources
Reputable organizations and medical references for learning more about Alagille Syndrome, including disease registries, foundation resources, and clinical guidelines.