PK-deficiency is an autosomal recessive disorder. As there is a DNA-test available, both carriers and affected cats can be diagnosed. PK-def has manifestated itself in the Abyssinian and Somali breeds, but has also been previously reported in at least 15 additional cat breeds. The PK-def associated variant was found at 3.1% and 2.2% in the Abyssinian and Somali breeds respectively. For these breeds PawPeds recommends the following routines:
- Only cats with known PK-status should be used for breeding.
- Carriers could be used for breeding but only be used for mating with cats that are normal with respect to the PK-mutation.
- Affected cats (with both PK-genes defective) should not be used for breeding.
The gene can also be found in other breeds. PK-deficiency testing can be performed on several breeds including Bengals, Egyptian Maus, La Perms, Maine Coon cats, Norwegian Forest cats, Savannahs, Siberians, and Singapuras, in addition to Abyssinians and Somalis. Breeds known to have been derived from Abyssinian crosses such as the Ocicat and novel breed development or out-crossing programs using Bengals or other affected breeds can be tested as well.
As for today, it's unclear how much of a risk there is that a cat who is homozygous for the PK-trait becomes ill. There is known that cats do get seriously ill from it, but also that cats go through their entire life without any problems at all. As for the other breeds it is unknown what the frequency is within each breed and there are no hard signals so far that this has become a problem within these breeds, the focus of breeders should rather be on more important health programmes. However, since this test is part of a lot of combibreeds test, avoiding the risk of mating two carriers is desirable to be on the safe side. Testing can be helpful to learn more about the expression of PK-deficiency and the frequency within each breed, so breeders can keep it under control.