Variable expression of Alagille syndrome in a family with a new JAG1 gene mutation.

We report the case of a patient with tetralogy of Fallot with absent pulmonary valve and familial Alagille syndrome who successfully underwent cardiac repair. The patient's sister had liver and congenital heart disease. The father had undergone liver transplantation but showed no significant cardiac abnormalities. A yet-unknown mutation of the JAG1 gene was discovered in this family with variable expression of Alagille syndrome.