Moyamoya vascular pattern in Alagille syndrome.

We describe a girl with Alagille syndrome and a moyamoya angiographic pattern on magnetic resonance angiography. She was referred for genetic consultation because of posterior embryotoxon and peripheral pulmonary stenosis. Her facial appearance was typical, but she had no cholestasis or vertebral involvement. A heterozygous duplication of one nucleotide (a c.715dupA mutation) not previously described was identified in exon 5 of the JAG1 gene. We review similar cases in the literature and possible pathophysiologic mechanisms (e.g., the Jagged 1 and Notch signaling pathway) of this association.