JAG1 and Alagille syndrome: Alagille syndrome is a heritable form of chronic liver disease in childhood associated with a mutation in JAG1. Patients with this syndrome have hypoplastic intrahepatic bile ducts with patent extrahepatic bile ducts [7-9] Other findings of the syndrome can include congenital heart disease, characteristic facial features, butterfly vertebrae, growth retardation, renal abnormalities, abnormal eye findings, pancreatic disease, and intracranial hemorrhage [7-9].