An autosomal dominant MUTATION involving CHROMOSOME 20. It is characterized by the almost normal LIVER that has few or no intrahepatic bile ducts (BILE DUCTS, INTRAHEPATIC). Other extrahepatic malformations include those in the heart, the eyes, the vertebral column, and the facies. Major clinical features include JAUNDICE, and congenital heart disease with peripheral PULMONARY STENOSIS.
