Peters anomaly is a disorder of the eye which involves thinning and clouding of the cornea and attachment of the iris to the cornea, which causes blurred vision. It may also be associated with clouding of the lens of the eye (cataracts) or other lens abnormalities. The cause of Peters anomaly is unknown; it may be caused by genetic factors (including alterations of several genes, like the FOXC1, PAX6, PITX2, or CYP1B1 genes, environmental factors, or both. The critical event must occur in the first trimester of pregnancy during the formation of the anterior chamber.Most cases of Peters anomaly are sporadic or inherited in an autosomal recessive pattern. Some few cases might be inherited in an autosomal dominant pattern.Peters anomaly may occur as an isolated ocular abnormality or in association with other ocular defects. Peters anomaly is a feature of the Krause-Kivlin syndrome and the Peters-plus syndrome. Treatment depends on the problems that the patient has and may include glaucoma treatment or surgery to correct the cataracts or other lens abnormalities.

While the exact cause of Peters anomaly is not known, the critical event is believed to occur in the first trimester of pregnancy, during the formation of the anterior chamber (the front part of the eye). Genetic and environmental factors may play a role. Some cases of Peters anomaly have been tied to mutation in the PAX6 gene, the PITX2 gene, the CYP1B1 gene, or the FOXC1 gene.These genes are all members of a family called homeobox genes that direct the formation of many parts of the body, like the anterior segment of the eye and mutations can lead to severe developmental problems, such as incomplete separation of eye structures and complete corneal opacity, or they can result in minor eye abnormalities including small, faint opacities. It is likely that mutations that cause a complete absence of protein function result in the most severe eye problems. In many cases of Peters anomaly, there is no mutation identified in any of these four genes. The cause of the condition in these cases is unknown.

Most cases of Peters anomaly are sporadic or autosomal recessive, but autosomal dominant transmission has been reported.