Categories: Vision / eye phene

Links to MONDO diseases: No links.

Mendelian trait/disorder: unknown

Considered a defect: yes

Species-specific symbol: ISD

Species-specific description: Genetics Committee of the American College of Veterinary Opthalmologists: "Defective development of the iris, or part of the iris, resulting in an immature state. ISD [Iris sphincter dysplasia] is the result of poorly developed iris sphincter muscles. The pupils of dogs with ISD do not properly contract in bright light. Dogs usually are uncomfortable and often squint in sunlight. The disorder exposes the interior of the eye to ultraviolet light that may potentially cause serious vision problems, such as cataracts or retinal damage, as dogs age."

Breed: Dalmatian.