Purpose
Peters anomaly represents a broad spectrum of central posterior corneal abnormality with variable adhesion to the iris and/or lens. Recessive CYP1B1 mutations are the only reported genetic cause on the Arabian Peninsula, where 92% of newborn glaucoma is CYP1B1-related. As part of our ongoing study to characterize Peters anomaly in Saudi Arabia, we report phenotypes and results of candidate gene sequencing for a consecutive cohort of affected children.
Methods
Review of clinical features and candidate sequencing results (PAX6, FOXE3, PITX2, FOXC1, CYP1B1) for a consecutive cohort of phenotyped Peters anomaly patients (2012-2014); review of clinical features described in previously-reported CYP1B1-related Peters anomaly phenotypes.
Results
43 subjects (33 bilateral; 36 families; 26 boys) are included. Pathogenic mutation was found in only one subject - homozygous p.G61E CYP1B1 mutation in a delayed boy with bilateral dense central circumscribed corneal opacity, iridocorneal adhesions, and glaucoma. This specific ocular phenotype was unique in our series but was the recurrent phenotype for the 8 previously-reported CYP1B1-related Peters anomaly cases. The 42 other subjects in our series had mild to severe corneal opacities, corneal-iridal and/or corneal-lenticular adhesions, and variable colobomatous microphthalmos (6), glaucoma (5), long philtrum/thin upper lip (17), abnormal ears (6), developmental delay (4), and/or congenital heart defects (2).
Conclusions
Although CYP1B1 mutations commonly underlie newborn glaucoma on the Arabian Peninsula, most encountered Peters anomaly phenotypes in the region are not related to mutations in the gene. There are likely other genetic causes yet to be described, particularly for the familial cases. CYP1B1-related Peters anomaly is characterized by bilateral congenital dense central circumscribed corneal opacity with glaucoma.