Alagille syndrome is an autosomal dominant disease characterized by pathogenic variants in the JAG1 and NOTCH2 genes. It occurs in 1:30,000 to 1:50,000 live births. It is a multisystem disorder with a wide spectrum of clinical variability. The major clinical manifestations of ALGS are bile duct paucity on liver biopsy, cholestasis, congenital cardiac defects (primarily involving the pulmonary arteries), butterfly vertebrae, ophthalmologic abnormalities (most commonly posterior embryotoxon), and characteristic facial features. Renal abnormalities, growth failure, splenomegaly, retinal changes, and vascular abnormalities may also occur.
JAG1