Primary hyperoxaluria / PH1 (AGXT-related) - Coton de Tulear

What does this test examine?

This genetic test analyses the AGXT c.304G>A variant in the Coton de Tulear. The disorder is also known as primary hyperoxaluria type 1, PH1, familial oxalate nephropathy and Oxalosis I.

The AGXT gene encodes alanine-glyoxylate aminotransferase, a liver enzyme that helps prevent glyoxylate from being converted into excessive oxalate. Dogs with two copies of the tested variant produce too much oxalate, allowing calcium oxalate crystals to damage mainly the kidneys and urinary tract.

What does this disorder mean?

Affected puppies can develop severe signs at a young age, including abdominal pain, vomiting, poor growth, increased drinking and urination, blood in the urine, urinary obstruction, kidney stones or acute kidney failure. The condition can become serious quickly and is highly relevant for health and breeding plans.

Practical value of this test

This DNA test is especially useful for breeders because carriers usually look healthy. Testing before breeding makes it possible to avoid carrier-to-carrier matings while still using carrier animals responsibly with clear dogs.

• Clear: the dog does not carry the tested variant and will not pass it on.
• Carrier: the dog carries one copy and can pass the variant on without becoming ill from that single copy.
• Genetically affected: the dog carries two copies and develops primary hyperoxaluria due to this variant.

The result gives breeders, buyers and veterinarians clear genetic information and helps keep severe early kidney disease caused by this known variant out of breeding lines.