Cystinuria results from a defect in the reabsorption of amino acids (COLA: cysteine, ornithine, lysine, arginine) in the proximal renal tubules. Cystinuria has been observed in more than 65 breeds of dogs. In cystinuria, cystine stones form in the bladder (urolithiasis). On average, the disease appears in dogs at the age of 5 years (2 - 7 years). Over 90 % of affected animals are male. Due to the anatomical conditions, significantly more male dogs present to the veterinary practice, as the stones can obstruct the male urethra.

Cystinuria has a hereditary background. In dogs, different modes of inheritance are known for cystinuria. Mutations for cystinuria have been identified in genes coding for the amino acid transport system b0, + (SLC3A1 and SLC7A9).   

Cystinuria in dogs is divided into 3 types depending on the inheritance pattern:

Type I-A

- Inheritance autosomal recessive (affected animals carry two defect alleles)

- Newfoundland, Landseer, Labrador Retriever

- caused by mutations in the SLC3A1 gene

- severe and early-manifest form (from puppy age or in young dogs)

- both sexes affected

Type II-A

- Inheritance autosomal dominant (affected animals carry one or two defect alleles)

- Australian Cattle Dog

- caused by mutations in the SLC3A1 gene

- severe and early-manifesting form (from puppy age or in young dogs)

- both sexes affected

Type II-B

- autosomal dominant inheritance (affected animals carry one or two defect alleles)

- Miniature Pinscher

- caused by mutations in the SLC7A9 gene

- both sexes affected

Type III

- milder and late-manifest form

- only males affected

- No mutation known so far

- a modifying androgen effect is suspected

- More than 60 breeds: Mastiff, French Bulldog,

  Basset, Irish Terrier, Scottish Deerhound, etc.

Aims of the project

Establishment of a bio-bank for dog breeds with cystinuria

Genetic analyses

Analysis of candidate genes leading to cystinuria by sequencing the corresponding regions in the genome

Practical application: development of a genetic test

Which breeds are we particularly interested in?

  •     Kromfohrländer
  •     Irish Terrier
  •     Scottish Deerhound
  •     Dachshund
  •     English Bulldog
  •     French Bulldog
  •     Basset
  •     Kooikerhondje
  •     Mastiff
  •     Tibetan Spaniel

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