PK Def Tests Results Explained and How it Will Affect Your Kitten.
Not to be confused with PKD, which stands for Polycystic Kidney Disease, all responsible breeders will have had their cats tested for PK Def, which is done by a simple mouth swab sample being sent to a Laboratory licensed to run the test. In the UK, the leading centre for this is Langford University. The test shows one of 3 results for the tested cat, remembering it is not infectious:
N/N = Normal - A Normal autosomal recessive PK Def genetic test result means that the cat does not have the genetic mutation causing pyruvate kinase deficiency.
N/K = Carrier - A Heterozygous autosomal recessive PK Def genetic test result means the cat has one copy of the mutation. The cat will not have pyruvate kinase deficiency but may pass the mutation to their offspring.
K/K = Affected or Positive—A Homozygous autosomal recessive PK Def genetic test result means the cat has two copies of the mutation, which means it will have pyruvate kinase deficiency.
How do these results affect my kitten?
Positive kitten – Though this kitten is affected with PK Def, it does not necessarily mean this is a death sentence.
In most cases, these cats will live everyday life spans and eventually die from age-related conditions. However, some may occasionally show clinical signs such as anaemia and lethargy. Still, these may be intermittent, and the cat may recover perfectly from such episodes without any veterinary intervention. In fact, they may be so fleeting that the owner isn’t aware of them. It will be prudent to have any clinical signs checked out by your vet (who should be made aware of the cat’s PK Def status) so that intervening treatment can be given. These positive cats should ideally not be bred from and should be homed as pets, though extremely exceptional circumstances may require them to have a litter to preserve a breeding line; however, we, personally, would never breed K/K kittens even to maintain a line because it does require production of K/K kittens.
Carrier kitten—These kittens will never display clinical signs of PK Def as they merely carry the gene, which could be passed onto their kittens. As pets, these carrier cats will never become ill with PK Def. However, these carrier cats can be very important in a breeding programme when a line must be preserved and mated to a Clear Cat.
Clear kitten—These kittens will never display clinical signs of PK Def and, when mated to other clear cats, will only produce clear kittens. These cats are the most important group to enable the breed to eventually become clear of PK Def.
When buying your kitten, it is a good idea to check that the parents have been tested and that you are freely offered a copy of the test certificate before committing to purchase the kitten. If either parent has tested Positive or is a Carrier, it will not be unreasonable to ask for the kitten to be tested before committing yourself.
Any responsible breeder will have already done this or be willing to have the test done. However, these tests may have been done early on in the kitten’s life to enable the breeder to plan if they wish to keep one for breeding. It may have been too soon to have microchipped the kitten before the swab test, so to ensure that your kitten's status is as stated by the breeder, it may be prudent to ask for the kitten to be tested again. However, this additional test may be at the purchaser’s expense. However, as it is a one-off test for life, it will be a small price to pay to know the kitten’s status. If both parents are tested as Clear, then the kittens will also be clear, so in this case, if you wish to have the kitten tested as well, the purchaser may be asked to fund the cost of such a test.
If you are considering buying a kitten for breeding, then you must know the kitten’s status. Hopefully, with carefully planned breeding programmes and testing, the Savannah will eventually be declared free of PK Def. In the meantime, if you are buying a pet:-
REMEMBER, A CARRIER KITTEN IS AS HEALTHY AS A CLEAR KITTEN; IT WILL HAVE NO HEALTH ISSUES FROM PYRUVATE KINASE DEFICIENCY!