The eye maintains normal pressure through a continuous balance between production and drainage of a clear fluid called aqueous humor. This fluid drains through a structure known as the iridocorneal angle. In dogs affected by POAG, genetic mutations interfere with the normal function or structure of this drainage pathway. As a result, fluid accumulates inside the eye, gradually increasing pressure. Over time, this elevated pressure damages the optic nerve, which is responsible for transmitting visual information from the eye to the brain.
Clinical signs of POAG often develop slowly, making early detection difficult without screening. In the early stages, dogs may show subtle symptoms such as mild eye redness, occasional discomfort, increased blinking, or watery discharge. As intraocular pressure rises, more noticeable signs may appear, including corneal cloudiness, pupil dilation, reduced vision, and behavioral changes such as hesitation in unfamiliar environments or bumping into objects. In advanced stages, the eye may become enlarged (buphthalmos), and irreversible blindness can occur due to optic nerve damage.
The POAG DNA Health Test is designed to detect the specific genetic mutation(s) associated with Primary Open Angle Glaucoma. The test is simple, safe, and non-invasive, typically performed using a cheek swab or blood sample. The collected DNA is analyzed in a specialized laboratory to determine whether the dog carries zero, one, or two copies of the mutation. Because DNA remains stable throughout life, testing can be performed at any age, including before clinical signs develop.
Results are generally reported in three categories:
- Clear (Normal): The dog does not carry the POAG mutation and is not expected to develop this genetic form of glaucoma or pass it to offspring.
- Carrier: The dog carries one copy of the mutation and may not show clinical signs but can pass the mutation to future generations.
- Affected/At Risk: The dog carries two copies of the mutation and has a significantly increased likelihood of developing Primary Open Angle Glaucoma.
Genetic testing for POAG provides valuable insight for breeders, veterinarians, and dog owners. Breeders can use results to make informed mating decisions that help reduce the prevalence of inherited glaucoma while preserving genetic diversity within the breed population. Avoiding carrier-to-carrier breeding significantly reduces the risk of producing affected puppies.
For dog owners, knowing a dog’s genetic status allows for proactive eye health monitoring and early veterinary intervention. Dogs identified as at risk should receive regular ophthalmic examinations to monitor intraocular pressure and detect early changes. While there is no cure for optic nerve damage caused by glaucoma, early treatment—such as pressure-lowering medications, laser therapy, or surgical procedures—can help slow progression and preserve vision for as long as possible.
The Primary Open Angle Glaucoma (POAG) Health Test is a reliable genetic screening tool that supports responsible breeding practices, promotes canine eye health, and helps reduce the impact of this inherited cause of blindness in future generations.
