The genetics and ocular findings of Alagille syndrome.

Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, Harvard Medical School, 243 Charles Street, Boston, MA 02114, USA.
Seminars in Ophthalmology (Impact Factor: 1.2). 01/2007; 22(4):205-10. DOI: 10.1080/08820530701745108
Source: PubMed

ABSTRACT Alagille syndrome is an autosomal dominant disorder caused by mutations in the JAG1 gene. The JAG1 gene encodes a ligand for the Notch receptor and thus is part of a critical signaling pathway during development. The ophthalmologist can play an important role in the diagnosis of Alagille syndrome by identifying the characteristic ocular findings. These include a posterior embryotoxon, optic disc drusen, angulated retinal vessels, and a pigmentary retinopathy. Despite recent advances in the genetics of Alagille syndrome, the correlations between genotypes and phenotypes remain incompletely defined.

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