--- license: permission_granted topic_id: companion_breed_health_labrador_retriever_cystine_urolithiasis_dog category: companion-breed-health title: "Labrador Retriever — Cystine urolithiasis (hereditary; OMIA-verified breed predisposition)" lang: en source: "OMIA (Online Mendelian Inheritance in Animals, University of Sydney) breed-specific hereditary-disorder record, saved verbatim to source_file; C1 substring-verified. Pulled 2026-08-02 from local OMIA database dump." source_file: pdf-raw/breed-health/labrador_retriever_cystine_urolithiasis_497.txt date_parsed: 2026-08-02 tokens_estimated: 973 verification: method: substring_match claims: 9 passed: 9 date: 2026-08-02 recovered: false path: companion-breed-health/companion_breed_health_labrador_retriever_cystine_urolithiasis_dog/01_companion_breed_health_labrador_retriever_cystine_urolithiasis_dog.md source_document: "OMIA — Online Mendelian Inheritance in Animals (University of Sydney)" citation: authority: "OMIA — Online Mendelian Inheritance in Animals (University of Sydney)" title: "Labrador Retriever — Cystine urolithiasis (hereditary; OMIA-verified breed predisposition)" url: "https://omia.org/OMIA000256/9615/" retrieved: "2026-08-02" ref: "OMIA breed-specific hereditary-disorder records (omia.org), derived from local OMIA database dump; dataset: https://doi.org/10.25910/2AMR-PV70" doc_type: "academic animal-genetics database (breed-specific disorder entries)" needs_review: false
Labrador Retriever — Cystine urolithiasis (hereditary; OMIA-verified breed predisposition)
Source: first-hand OMIA (University of Sydney) breed-specific hereditary-disorder record, saved verbatim to source_file; every claim below is a C1 byte-substring of it.
Claims
Breed: Labrador Retriever (Dog)Disorder: Cystine urolithiasisMode of inheritance: Autosomal recessiveSummary: Cystinuria, type 1 - A is an inherited defect that causes failure of reabsorption of cystine in the proximal renal tubule, leading to cystine precipitation in the urine. Formation of crystals and calculi lead to urolithiasis and urinary tract obstruction. The disorder is inherited as an autosomal recessive trait and it is caused by a mutation in SLC3A1. Edited by Dr. Paula Henthorn (modified by IT 23/5/2022 and 29/3/2023)Clin feat: Presenting signs include recurrent cystitis, hematuria, and stranguria. Calculi may become lodged in the urinary bladder, urethra, or kidney, causing partial or complete urinary blockage, which can result in renal failure (Brons et al., 2013). A relatively earlier age of onset has been identified in Newfoundlands compared to other breeds that develop cystinuria. Diagnosis is achieved by identifying characteristically hexagonal cystine crystals in urine sediment, or cystine calculi in stone analysis. Metabolic screening tests on urine (cyanide nitroprusside test, amino acid chromatography or amino acid quantification) can detect cystinuria before or after clinical onset. Since cystine easily precipitates in acidic urine to form uroliths, treatment includes alkalinization of the urine, high fluid intake, and drugs that increase cystine solubility (Harnevik et al., 2006). As summarised by Brons et al. (2013), Cystinuria type I - A is characterised by: occurs in males and females; not androgen-dependent; COLA [μmol/g creatinine (normal ≤500)] ≥8,000 in homozygotes and ≤500 in heterozygotes.Defect: yesPathology: Cystinuria is caused by a defect in amino acid transport in epithelial cells of the proximal tubule of the nephron and gastrointestinal epithelium. The relevant amino acids (cystine, ornithine, lysine, and arginine) are transported by a heteromeric amino acid transporter encoded by the genes SLC3A1 and SLC7A9. Clinical signs are caused by failure of reabsorption of these amino acids, leading to precipitation in the urine. In the case of cystine, it readily reaches saturation concentration in urine, which can be exacerbated by a low urinary pH. Formation of crystals and calculi lead to urolithiasis, recurrent cystitis and urinary tract obstruction. Although the transport defect also occurs in the intestine, there is no associated nutritional deficiency.Prevalence: Cystinuria is most commonly identified in male dogs, and rarely seen in female dogs. In at least one breed, this is due to the differences in the anatomy of the urethra in males and females. Cystinuria has been most extensively studied in Newfoundlands (Henthorn et al., 2000), but various forms of cystinuria have been recognized in over 60 breeds (Osborne et al., 1999).Control: Affected Newfoundlands are homozygous for the c.586CT mutation, but homozygous females may be undetected clinically. Heterozygous Newfoundlands are unaffected carriers. All progeny of affected male and female Newfoundlands are carriers. It is recommended to avoid breeding that may result in affected dogs. Should carriers be bred to noncarriers, all offspring should be tested. Fitzwilliams et al. (2023) identified allele frequencies of 0.40 and 0.40 in English bulldogs from Denmark for the c.574AG and c.2092AG variants, respectively. The authors state: “Due to high allele frequencies, limited genetic diversity, continued uncertainty about the genetic background of cystinuria, and more severe health problems in the [English bulldog] breed, selection based on genetic testing for the mutations in SLC3A1 cannot be recommended in the Danish population of English bulldogs. However, results of the genetic test may be used as a guide to recommend prophylactic treatment.”
Associated gene(s)
Derived from OMIA database dump (omia.xml, local); structured field, not verbatim prose. First-hand values below are verbatim substrings of the topic's pdf-raw/omia/<phene_id>.txt source file.
- Gene: Entrez Gene ID 403700 (no symbol in OMIA GeneSynonym) — OMIA Phene_Gene
Evidence (references)
Derived from OMIA database dump (omia.xml, local); structured field, not verbatim prose. First-hand values below are verbatim substrings of the topic's pdf-raw/omia/<phene_id>.txt source file.
- 1936. Canine cystinuria. III. Journal of Biological Chemistry — OMIA Phene_Article / Article
- 1940. Canine cystinuria V. Family history of two cystinuria dogs and cystine determinates in dog urine. Journal of Biological Chemistry — OMIA Phene_Article / Article
- 1993. Canine cystinuria - something old, something new. British Veterinary Journal — PubMed:PMID8334504 | DOI:10.1016/S0007-1935(05)80167-8 — OMIA Phene_Article / Article
- 1993. Urinary excretion of amino acids in normal and cystinuric dogs. British Veterinary Journal — PubMed:PMID8334507 | DOI:10.1016/S0007-1935(05)80171-X — OMIA Phene_Article / Article
- 1993. Canine cystinuria - An extended study on the effects of 2- mercaptopropionylglycine on cystine urolithiasis and urinary cystine excretion. British Veterinary Journal — PubMed:PMID8334506 | DOI:10.1016/S0007-1935(05)80170-8 — OMIA Phene_Article / Article
- 1995. Inheritance of cystinuria and renal defect in Newfoundlands. J Am Vet Med Assoc — PubMed:PMID7493896 — OMIA Phene_Article / Article
- 1999. Canine cystine urolithiasis. Cause, detection, treatment, and prevention. Vet Clin North Am Small Anim Pract — PubMed:PMID10028158 | DOI:10.1016/s0195-5616(99)50011-9 — OMIA Phene_Article / Article
- 2000. Canine cystinuria: polymorphism in the canine SLC3A1 gene and identification of a nonsense mutation in cystinuric Newfoundland dogs. Human Genetics — PubMed:PMID11129328 | DOI:doi: 10.1007/s004390000392 — OMIA Phene_Article / Article
- 2001. Cystinuria in the dog: Clinical studies during 14 years of medical treatment. J Vet Intern Med — PubMed:PMID11467594 — OMIA Phene_Article / Article
- 2009. Canine and feline urolithiasis: examination of over 50 000 urolith submissions to the Canadian veterinary urolith centre from 1998 to 2008. Can Vet J — PubMed:PMID20190975 — OMIA Phene_Article / Article
- 2006. SLC7A9 cDNA cloning and mutational analysis of SLC3A1 and SLC7A9 in canine cystinuria. Mamm Genome — PubMed:PMID16845473 | DOI:10.1007/s00335-005-0146-4 — OMIA Phene_Article / Article
- 2006. Efficient screening of the cystinuria-related C663T Slc3a1 nonsense mutation in Newfoundland dogs by denaturing high-performance liquid chromatography. J Vet Diagn Invest — PubMed:PMID16566266 | DOI:10.1177/104063870601800116 — OMIA Phene_Article / Article
- (7 additional references in OMIA)
Comparative medicine (human OMIM)
Derived from OMIA database dump (omia.xml, local); structured field, not verbatim prose. First-hand values below are verbatim substrings of the topic's pdf-raw/omia/<phene_id>.txt source file.
- OMIM:220100 (type: trait) — OMIA Group_OMIM (via OMIA_ID)
- OMIM:104614 (type: gene) — OMIA Group_OMIM (via OMIA_ID)
verification_derived: method: derived_from_dataset source: "OMIA database dump (omia.xml, local); fields Gene/Variant/Article/OMIM" note: "Structured fields (gene, variant rsID/protein change, PubMed/DOI references, OMIM cross-link) extracted from OMIA dump and presented with first-hand values; not verbatim prose."