Polycystic kidney disease (PKD) is a hereditary disease which can be tested with a DNA test for cats. Polycystic kidney disease in cats is inherited disease of Persian cats and related breeds. Around 38% of Persian cats carry a mutation in PKD gene which is around 6% of total domestic cat population, thus making this disease most common genetic disorder in cats. The mutation in PKD1 gene is causing liver and kidney cysts filed with fluid that usually lead to kidney failure. Cysts can form sporadically in any cat breed, however in carriers of the mutation the onset of cysts is early and they are usually present in both kidneys. In cats with the genetic mutation they are present as early as 12 month of age, however kidney failure is seen much later in life, therefore this disease is characterised as a late kidney disease. Presence of cysts can be detected by ultrasound as early as 6 to 8 month of age, while the first clinical signs are usually apparent between first and second year of life. The average age of first kidney dysfunction in cats with PKD is 7 years; however in cats not examined by ultrasound the correct diagnosis is usually never established. Clinical signs are not specific and are similar to those that can be seen in other cats with kidney dysfunction: depression, anorexia, loss of appetite, polyuria and loss of weight.

Inheritance: autosomal dominant - read more

Mutation: PKD1 gene

Genetic test: The method used for genetic testing is extremely accurate and allows complete differentiation between affected animals, carriers and healthy dogs. DNA testing can be done at any age.

Disease control: Because this hereditary disease is autosomal dominant it will manifest itself in all animals carrying at least on mutated gene. Such heterozygous animals will show clinical signs that will decrease their quality of life. Because the hereditary disease has relatively late onset, diseased animals can have offspring that will have 50% chance of obtaining gene with mutation and therefore develop the disease, if heterozygous cat is mated with normal cat. So far homozygous animals carrying two mutations have not been found, suggesting such animals die of while developing. With the intention of eradication of the disease it is not advisable to breed diseased animals.

DNA test sample: EDTA whole blood (1.0 ml) or buccal swabs. Detailed information about sampling can be found here.