Alagille syndrome: an overview.

Alagille syndrome is an embryofoetopathy, due to mutations in the gene JAG1. It is autosomic dominant with variable expressivity, or sporadic. Neonatal cholestasis is a main feature, due to the paucity of intrahepatic bile ducts. It can rarely develop into cirrhosis, but be responsible for a disabling pruritus and xanthomas. The other features are a peculiar facies, cardiac abnormalities, butterfly vertebrae, and ocular embryotoxon. The prognosis depends on the severity of the liver and heart diseases. Hepatocarcinoma has been reported.