Glaucoma (Border Collie Type)

Common Symptoms

Glaucoma (border collie type) is an inherited eye disease affecting border collies. Affected dogs display malformations in an area of the eye known as the iridocorneal angle often resulting in increased eye pressure in both eyes. As the pressure in the eyes increases, they become painful. Signs of pain include excessive blinking, tearing and redness. If left untreated, increased pressure in the eyeball leads to enlargement, optic nerve damage, and the gradual loss of vision.

Breed-Specific Information for the Border Collie

The Mutation of the OLFML3 gene associated with Glaucoma (border collie type) has been identified in border collies. Though the exact frequency in the overall border collie population is unknown, in one study approximately 8.3% out of 350 border collies tested were carriers of the mutation and 0.6% were at-risk.

Testing Tips

Genetic testing of the OLFML3 gene in border collies will reliably determine whether a dog is a genetic Carrier of Glaucoma (border collie type). Glaucoma (border collie type) is inherited in an Autosomal Recessive manner in dogs meaning that they must receive two copies of the mutated gene (one from each parent) to develop the disease. In general, carrier dogs do not have features of the disease but when bred with another carrier of the same Mutation, there is a risk of having affected pups. Each pup that is born to this pairing has a 25% chance of inheriting the disease and a 50% chance of inheriting one copy and being a carrier of the OLFML3 gene mutation. Reliable genetic testing is important for determining breeding practices. Because symptoms may not appear until adulthood, genetic testing should be performed before breeding. In order to eliminate this mutation from breeding lines and to avoid the potential of producing affected pups, breeding of known carriers to each other is not recommended. Border collies that are not carriers of the mutation have no increased risk of having affected pups.

There may be other causes of this condition in dogs and a normal result does not exclude a different mutation in this gene or any other gene that may result in a similar genetic disease or trait.

References

• Oliver JAC, Wright H, Massidda PA, Burmeister LM, Mellersh CS. A variant in OLFML3 is associated with pectinate ligament abnormality and primary closed‐angle glaucoma in Border Collies from the United Kingdom. Vet Ophthalmol. 2019 May 29. doi: 10.1111/vop.12680. PubMed: 31141290 [PubMed: 31141290]
• Pugh CA, Farrell LL, Carlisle AJ, Bush SJ, Trejo-Reveles V, Matika O, de Kloet A, Walsh C, Bishop SC, Prendergast JGD, Schoenebeck JJ, Rainger J, Summers KM. Arginine to glutamine mutation in olfactomedin-like 3 (OLFML3) is a candidate for severe goniodysgenesis and glaucoma in the Border Collie dog breed. G3 (Bethesda). 2019 Mar 7;9(3):943-954. doi: 10.1534/g3.118.200944. PubMed: 30696701 [PubMed: 30696701]