Breeds Affected: Domestic shorthair
Samples Accepted: Blood, Buccal Swabs
Disease Information: Primary Hyperoxaluria leads to a build-up of oxalate (oxalic acid) in the body of affected cats, which can then deposit in the kidney as calcium oxalate crystals. In addition to the problem with blockages, the kidneys cannot concentrate properly, leading to death by acute renal failure at under a year of age.
Inheritance Information: Primary Hyperoxaluria (PH2) is autosomal recessive, meaning that animals with two copies of this allele will be affected. Animals with one copy of the gene will be clinically-normal carriers.
The possible genotypes are:
N/N The cat is normal, and cannot produce affected offspring.
N/ph2 The cat is a carrier, and can pass the allele on to approximately 50% of any offspring. If bred to another N/ph2 carrier, approximately 25% of the offspring will be normal, 50% will be carriers, and 25% will be affected.
ph2/ph2 The cat is affected. If bred to a normal animal, 100% of the offspring will be carriers. If bred to an N/ph2 carrier, 50% of the offspring will be carriers and 50% will be affected.
– Carriers may be bred to normal animals (N/ph2 x N/N) without any risk of producing affected offspring. The offspring should be tested before breeding to determine if they are carriers or normal.
– Breeding two carriers (N/ph2 x N/ph2) is not recommended due to the possibility of 25% of the offspring being affected.
– Affected animals (ph2/ph2) should not be used for breeding.
Test Information: This mutation test identifies a single base change in the GRHPR gene.
Goldstein, RE., Narala, S., Sabet, N., Goldstein, O., McDonough, SP.: Primary Hyperoxaluria in Cats Is Caused by a Mutation in the Feline GRHPR Gene. J Hered 100 (Suppl. 1):S2-S7, 2009. Doi: 10.1093.jhered/esp038.
Further information is available at the Online Mendelian Inheritance in Animals website.