A rare, genetic, primary bone dysplasia syndrome characterized by bilateral, painless swelling of the face extending from the mandible to the inferior orbital margins (cherubism), epilepsy, gingival fibromatosis (possibly obscuring teeth), and intellectual disability. Other associated variable features include hypertrichosis, stunted growth, juvenile rheumatoid arthritis, and development of ocular abnormalities (e.g. pigmentary retinopathy, optic disc pallor, Axenfeld anomaly). Radiological images typically show bilateral multifocal radiolucency involving the body, angle and ramus of the mandible and coronoid process.

Anterior segment dysgeneses (ASGD or ASMD) are a heterogeneous group of developmental disorders affecting the anterior segment of the eye, including the cornea, iris, lens, trabecular meshwork, and Schlemm canal. The clinical features of ASGD include iris hypoplasia, an enlarged or reduced corneal diameter, corneal vascularization and opacity, posterior embryotoxon, corectopia, polycoria, an abnormal iridocorneal angle, ectopia lentis, and anterior synechiae between the iris and posterior corneal surface (summary by Cheong et al., 2016). Anterior segment dysgenesis is sometimes divided into subtypes including aniridia (see 106210), Axenfeld and Rieger anomalies, iridogoniodysgenesis, Peters anomaly, and posterior embryotoxon (Gould and John, 2002). Some patients with ASGD3 have been reported with the following subtypes: iridogoniodysgenesis, Peters anomaly, Axenfeld anomaly, and Rieger anomaly. Iridogoniodysgenesis, which is characterized by iris hypoplasia, goniodysgenesis, and juvenile glaucoma, is the result of aberrant migration or terminal induction of the neural crest cells involved in the formation of the anterior segment of the eye (summary by Mears et al., 1996). Peters anomaly consists of a central corneal leukoma, absence of the posterior corneal stroma and Descemet membrane, and a variable degree of iris and lenticular attachments to the central aspect of the posterior cornea (Peters, 1906). In Axenfeld anomaly, strands of iris tissue attach to the Schwalbe line; in Rieger anomaly, in addition to the attachment of iris tissue to the Schwalbe line, there is clinically evident iris stromal atrophy with hole or pseudo-hole formation and corectopia (summary by Smith and Traboulsi, 2012).

Alagille syndrome (ALGS) is a multisystem disorder with a wide spectrum of clinical variability; this variability is seen even among individuals from the same family. The major clinical manifestations of ALGS are bile duct paucity on liver biopsy, cholestasis, congenital cardiac defects (primarily involving the pulmonary arteries), butterfly vertebrae, ophthalmologic abnormalities (most commonly posterior embryotoxon), and characteristic facial features. Renal abnormalities, growth failure, developmental delays, splenomegaly, and vascular abnormalities may also occur.

Distal monosomy 6p is responsible for a distinct chromosome deletion syndrome with a recognizable clinical picture including intellectual deficit, ocular abnormalities, hearing loss, and facial dysmorphism.

Foveal hypoplasia is defined as the lack of foveal depression with continuity of all neurosensory retinal layers in the presumed foveal area. Foveal hypoplasia as an isolated entity is a rare phenomenon; it is usually described in association with other ocular disorders, such as aniridia (106210), microphthalmia (see 251600), albinism (see 203100), or achromatopsia (see 216900). All reported cases of foveal hypoplasia have been accompanied by decreased visual acuity and nystagmus (summary by Perez et al., 2014). For a discussion of genetic heterogeneity of foveal hypoplasia, see FVH1 (136520).