Cystinuria (SLC3A1) (Australian Cattle Dog Type)

Test Overview:

Cystinuria was one of the first identified inborn defects of metabolism. It is an inherited defect of renal transport that included malabsorption of cystine and the dibasic amino acids ornithine, lysine and arginine, collectively known as COLA. In dogs it has been reported for the first time in 1823 and today it is known to affect more than 70 dog breeds. In the normally functioning kidney, amino acids and some other substances are filtered out of the blood, and then reclaimed from the urine. Malabsorption of COLA amino acids in the proximal renal tubules causes their high concentrations in the urine of the affected individual. Main problems are caused by low solubility of cystine in urine of acidic and neutral pH. High concentrations of cystine in urine and its low solubility leads to cystine crystals and bladder stones formation, known as uroliths. Uroliths in the urinary tract can result in stranguria, hematuria, urinary obstruction and renal failure with possible fatal outcome. Symptoms of disease include straining to urinate, frequent urination or inability to urinate. In Labrador retrievers both males and females are affected, but obstruction of urine flow is more common in males due to differences in anatomy and females tend to develop stones later than males. Dogs with cystinuria often have recurrent inflammation of the urinary tract and if not treated, urinary stones can cause urinary tract infections, kidney failure and even death.


Urinary system / Urologic - Associated with the kidneys, bladder, ureters and urethra


Solute carrier family 3 member 1 (SLC3A1) on chromosome 10

Variant Detected:

Nucleotide Deletion c.1095-1100del p.366-367Thr 6bpdeletion (inframe)


Moderate. This disease can cause significant signs of discomfort and/or dysfunction in affected animals. It may involve relatively high treatment/management costs, and can sometimes reduce life expectancy.

Mode of Inheritance:

Autosomal Dominant with Incomplete Penetrance

Recommended Screening:

Breeding animals should be screened prior to entering into breeding programs.

Research Citation(s):

Brons AK, et al. SLC3A1 and SLC7A9 Mutations in Autosomal Recessive or Dominant Canine Cystinuria: A New Classification System. (2013) J vet intern med, 27(6);1400-1408

Associated Breed(s):

Australian Cattle Dog, Border Collie, Koolie , Mixed Breed, Smithfield,