Axenfeld-Rieger syndrome features can be divided into ocular and non-ocular findings. Ocular abnormalities mainly affect the iris: hypoplasia, corectopia or hole formation in the iris mimicking polycoria; cornea: prominent and anteriorly displaced Schwalbe's line (posterior embryotoxon); and the chamber angle: iris strands bridging the iridocorneal angle to the trabecular meshwork. Eye dysgenesis in ARS may cause increased ocular pressure (IOP) leading to glaucoma. Glaucoma can develop in infancy, but usually occurs in adolescence or early adulthood, occasionally after middle age. The most characteristic non-ocular findings are mild craniofacial dysmorphism, dental anomalies and redundant periumblical skin. Mid-face abnormalities include hypertelorism, telecanthus, maxillary hypoplasia with flattening of the mid-face, prominent forehead, and broad, flat nasal bridge. Dental abnormalities may include microdontia or hypodontia. Hypospadias in males, anal stenosis, pituitary abnormalities and growth retardation may also be observed.
Patients with ARS have been found to have mutations in the transcription factor genes PITX2 (4q25) and FOXC1 (6p25).
