Cystinuria (Labrador Retriever Type)
Affected Genes: SLC3A1
Inheritance: Autosomal Recessive
Variant(canFam6):
chr10:46562524: C>DEL
Breed: Australian Cobberdog
Australian Labradoodle
Labradoodle
Labrador Retriever
UK Breed Council Labrador Retriever
General Information: Cystinuria (Labrador Retriever Type) is an inherited kidney disease affecting various dog breeds, including Labrador Retrievers, Australian Labradoodles, Australian Cobberdogs, and UK Breed Council Labrador Retrievers. This condition results from mutations in the SLC3A1 gene, which encodes a protein critical for the reabsorption of cystine and other amino acids in the kidneys. Normally, cystine is reabsorbed in small amounts, but in affected dogs, the inability to reabsorb cystine leads to its accumulation in the urine. This excess cystine can form crystals or stones, which may obstruct the urinary tract and impede normal urine flow. Male dogs typically present with symptoms such as straining to urinate, frequent urination in small amounts, or inability to urinate between 6 to 14 months of age. Female dogs often develop symptoms later due to anatomical differences, usually about a year after males. If left untreated, cystinuria can lead to recurrent urinary tract infections, kidney failure, and potentially fatal complications. Early diagnosis and management are crucial to prevent severe health issues and maintain the affected dogs' quality of life.
How to Read Your Dog's Test Results for this Genetic Variant:
Two Variants Detected: Dog Likely Affected
One Variant Detected: Dog Unlikely Affected
No Variants Detected: No Effect
Gene / Testing Information: Genetic testing for the SLC3A1 gene is essential for identifying carriers of the mutation responsible for Cystinuria (Labrador Retriever Type) in dogs. This disorder is inherited in an autosomal recessive manner, meaning a dog must inherit two copies of the mutated gene, one from each parent, to develop the disease. Carrier dogs, which have only one copy of the mutation, typically do not show symptoms but can pass the gene to their offspring. When two carriers are bred, each puppy has a 25% chance of developing cystinuria and a 50% chance of being a carrier. Reliable genetic testing is crucial for responsible breeding practices to avoid mating two carriers, thereby reducing the risk of producing puppies with cystinuria. By identifying carriers and making informed breeding decisions, breeders can help eliminate this condition from the affected breeds, ensuring healthier and more robust future generations. It is important to note that while genetic testing for the SLC3A1 mutation reduces the risk of cystinuria, other genetic or environmental factors may still contribute to similar conditions, necessitating comprehensive genetic screening and careful management.
References:
Brons AK, Henthorn PS, Raj K, Fitzgerald CA, Liu J, Sewell AC, Giger U. SLC3A1 and SLC7A9 mutations in autosomal recessive and dominant canine cystinuria: A new classification system. J Vet Intern Med. 2013 27(6):1400-8.