Cairn Terrier Ocular Melanosis Project (MSU)
Research into Ocular Melanosis is currently being conducted by Dr. Simon Petersen-Jones and his team at Michigan State University (MSU), East Lansing. The Foundation of the Cairn Terrier Club of America is proud to help fund this research. The reports from this research can be found here:
Ocular Melanosis Research Report November 2024 >
Ocular Melanosis Research Report September 2024 >
Ocular Melanosis Research Report 2023 >
Ocular Melanosis Research Report 2020 >
Ocular Melanosis (OM)/Secondary Glaucoma
(Formerly referred to as Pigmentary Glaucoma)
Ocular Melanosis is an inherited condition that occurs predominantly in Cairn Terriers, although there are some unconfirmed reports of a similar condition in other breeds. Pigment deposits accumulate and decrease the eyes’ ability to drain fluid out of the anterior chamber. This fluid accumulation leads to an increase in pressure in the eye known as secondary glaucoma. The condition generally affects both eyes. If the elevated pressure goes undiagnosed and/or untreated, the dog will not only go blind, but also suffer from pain because of increased pressure in the eye.
Onset of the more obvious changes usually occurs between 7 to 12 years of age, which make this a vital time to closely watch each eye for small spots or patches of very dark pigmentation within the sclera (white part of the eye). Visits to the veterinarian when Cairns are this age should include an examination of the anterior chambers of the eyes for pigment deposits as well. It is important that all Cairns be checked regularly for the early signs of Ocular Melanosis (pigmented scleral patches and thickened iris roots) especially those dogs who are related to dogs that have, or that are suspected to have Ocular Melanosis.
If caught early, the damage that glaucoma causes can be slowed, and vision maintained longer by use of medications. If allow to persist, the condition may require removal of the eye due to the pain caused by a build-up of pressure.
Awareness of this condition in the United States is fairly recent, as the first known cases were diagnosed in 1984.
If your Cairn has been diagnosed with Ocular Melanosis and you would like more information, you may contact Dr. Petersen-Jones at peter31@cvm.msu.edu. He can also be contacted through the Comparative Opthalmology laboratory at MSU by telephone at (517) 353-3278.
Update on Ongoing Ocular Melanosis (OM)
Dr. Simon Petersen-Jones
November 17, 2024
Test
The test for the more common form of Ocular Melanosis is currently being finalized and tested prior to release. We are finalizing the number of markers that will be tested. This dictates the cost of running the test, so I don't have an accurate figure yet. We anticipate it being ready early next year now.
Future Investigation Plans
We would like to continue working to:
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Find the actual causal DNA change for the mapped form of OM.
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We also want to identify the cause of the second form of OM.
Achieving both aims will enable us to develop a combined test that should identify all OM at risk dogs. We are working on a more detailed proposal to outline the next steps for these aims.
What Else We Need
We would like to receive DNA samples from more affected dogs (confirmed by a veterinary ophthalmologist) and also from elderly dogs that have been examined by an ophthalmologist and confirmed free of OM.
We also would like to receive eyes that are removed form OM-affected dogs and also donor eyes from dogs that die for unrelated reasons.
Dr. Mellersh is sending us several DNA samples from affected and control Cairns in the UK. We are looking at our samples from other countries to see if they have the same division between the two forms of OM.
Click here for our published OM mapping paper >
The Research Team Needs:
Donated eyes, blood samples and pedigrees to conduct their research.
The linked documents below provide the information you’ll need to support this important Ocular Melanosis initiative.
This document is an overview of how to donate eyes under different circumstances:
OM Globe Donations >
These three documents describe the process depending on the timing of the eye removal:
OM collection for RNA >
OM formalin eye collection >
OM general eye collection >
The standard info form for incoming samples:
OM Info Form >
Information for shipping a blood sample:
OM Blood Collection Form >
If you have any questions about donations, please contact Dr. Paige Winkler Smith by email: eyeresearch@cvm.msu.edu