Anterior Segment Dysgenesis 8

Clinical Characteristics
Ocular Features: 

This is a congenital anterior segment dysplasia syndrome with considerable clinical heterogeneity.  Iris hypoplasia with transillumination, corectopia, iridodenesis, and iridocorneal adhesions are often seen.  Intraocular pressure may be elevated in older individuals.  Ectopia lentis is often present.  Lenticular opacities consisting primarily of posterior cortical opacification are common.  Visual acuity varies from 6/6 to 6/24.

No foveal hypoplasia is present but one of four reported patients was described with bilateral optic nerve dysplasia.     

Systemic Features: 

No systemic abnormalities have been reported.


Three families with 4 affected individuals with similar clinical features have been reported with homozygous or compound heterozygous mutations in the CPAMD8 gene (19p13.11).

A single male patient of native American/French Canadian background with somewhat similar clinical features has been reported with compound heterozygous mutations in the CYP1B1 gene (2p22.2) but this is likely a unique condition (Anterior Segment Dysgenesis 6).

The genes FOXE3 and PAX6 are characterized as transcription factors and play important roles in ocular development.  However, while mutations in these are frequently found in patients with dysgenesis of the anterior chamber they often cause more widespread ocular and systemic anomalies (e.g., Gillespie syndrome [206700]).  Therefore in this database the anterior chamber constellations of anomalies associated with mutations in these genes are not considered to be simplex conditions. 

See also related disorders iridogoniodysgenesis type 1 (601631) and type 2 (137600), and anterior segment mesenchymal dysgenesis (107250).

Treatment Options: 

Several patients have had cataract surgery.  Monitoring intraocular pressure throughout life is necessary and prompt treatment for glaucoma is important.

Article Title: 


Cheong SS, Hentschel L, Davidson AE, Gerrelli D, Davie R, Rizzo R, Pontikos N, Plagnol V, Moore AT, Sowden JC, Michaelides M, Snead M, Tuft SJ, Hardcastle AJ. Mutations in CPAMD8 Cause a Unique Form of Autosomal-Recessive Anterior Segment Dysgenesis. Am J Hum Genet. 2016 Dec 1;99(6):1338-1352.

PubMedID: 27839872