OM is inherited in the Cairn Terrier breed, with our pedigree analysis suggesting a dominant mode of inheritance. Unfortunately, we do not have a genetic test for OM, and the characteristic changes in the eyes may not be detected until middle-age, which is well after the dogs have been used for breeding. The lack of a genetic test and the appearance of the condition in middle-age makes it difficult to eradicate by selective breeding.

A main aim of our OM research is to identify the gene mutation that causes OM. We have made significant advances in this area of research, and our hope is that this will eventually enable us to develop a genetic test for the condition. Such a test could be used by breeders to select unaffected dogs for their breeding program and thus help reduce the incidence of the condition and eventually eradicate it completely.

Ocular melanosis affects both eyes and causes pigmented (i.e. black or brown) cells to accumulate in the eye. These appear as a thickening of part of the eye called the iris, and also lead to black spots or plaques that involve the white of the eye (the sclera).

Inside the eye, production of the pigment can eventually block the drainage pathway that is responsible for draining fluid from the eye (fluid is constantly produced in the eye and normally drains away into the blood stream, keeping the eye at a normal pressure). Interference with the normal fluid drainage causes the pressure inside the eye to increase. This can be painful, and causes damage in the eye that can result in blindness.

Ocular melanosis is diagnosed by a veterinarian who may consult of refer your dog to a specialist (veterinary ophthalmologist). Careful examination of the eyes can reveal whether a dog is affected or not. The diagnosis may not be made until the dog is several years of age. The changes may first be detected in middle age. Glaucoma can develop as early as about seven years of age, but will often not occur until much later. Some dogs have mild changes, and may not develop glaucoma.

There is no cure for canine ocular melanosis. Typical treatments include anti-inflammatory and pain medications, as well as medications to reduce the fluid produced in the eyes. Additionally, surgical intervention may be recommended for advancing cases with glaucoma.

Publications resulting from ocular melanosis research can be found through this link on PubMed.

This link is to a handout describing ocular melanosis.

Thank you for your interest in our ocular melanosis study. Please start by completing this ocular melanosis information form and submitting it to us by email to: eyeresearch@msu.edu.

Additionally, samples and specimen may be submitted to our office for use in this study. Please see the specific forms below for guidelines.

• Blood Collection
• Globe (eye) Donations – if the eye needs to be removed
• Globe (eye) Collection
  • General Collection
  • Collections for RNA
  • Formalin Collection