Cystinuria is an inherited disorder of renal transport characterised by high urine concentrations of cystine and other similar amino acids (ornithine, lysine, arginine). Excess cystine leads to formation of cystine crystals and stones in the urinary tract, which can result in urinary obstruction, haematuria and renal failure. Cats are juvenile to middle age when the first signs appear and there is an equal proportion of females and males. Recently 3 missense mutations in the SLC7A9 gene have been identified with a possibly autosomal recessive mode of inheritance. Just one out of three mutations is enough to cause cystinuria.
Mutations that have been discovered to date are not responsible for all cases of Cystinuria in cats. Most mutations to date have been detected in mixed breed cats so it is very difficult to determine which mutation can occur in a purebred cat.
Inheritance: autosomal recessive - read more
Mutation: SLC7A9 gene
Genetic test: The method used for testing is extremely accurate and allows complete differentiation between affected animals, carriers and healthy dogs. Testing can be done at any age.
Disease control: read more
Sample: EDTA whole blood (1.0 ml) or buccal swabs. Detailed information about sampling can be found here.