Cystinuria, type I-B

 

Gene: SLC7A9

Transmission: Autosomal recessive

For an autosomal recessive genetic disease an animal must have two copies of the mutation in question to be at risk of developing the disease.  Both parents of an affected animal must be carriers of at least one copy of the mutation.  Animals that have only one copy of the mutation are not at risk of developing the disease, but are carrier animals that can pass the mutation on to future generations.

Mutations:

 

Medical system: Renal

Breeds:

Age of onset of symptoms:

 

The classification and naming of canine cystinurias, as suggested by Brons et al. (2013), is based on the transmission (Type I for recessive, Type 2 for dominant) and the gene that is mutated (-A for the SLC3A1 gene, -B for the SLC7A9 gene), as follows:

Cystinuria Type I-A : Type I = recessive, -A = SLC3A1 gene

Cystinuria Type II-A : Type II = dominant, -A = SLC3A1 gene

Cystinuria Type I-B : Type I = recessive, -B = SLC7A9 gene

Cystinuria Type II-B : Type II = dominant, -B = SLC7A9 gene

 

References:

OMIA link: [0256-9615]

Donner J, Freyer J, Davison S, et al. (2023) Genetic prevalence and clinical relevance of canine Mendelian disease variants in over one million dogs.  PLoS Genet. 19(2):e1010651. [pubmed/36848397]

Fitzwilliams T, Wolff-Sneedorff, JL, Fredholm M, et al. (2023) Evaluation of the value of genetic testing for cystinuria in the Danish population of English bulldogs. Anim Genet 54(4):566-569.  [pubmed/36971195]

Kovaříková S, Maršálek P, Vrbová K. (2021) Cystinuria in dogs and cats: What do we know after almost 200 years? Animals (Basel) 11:2437.  [pubmed/34438894]

Brons AK, Henthorn PS, Raj K, et al. (2013) SLC3A1 and SLC7A9 mutations in autosomal recessive or dominant canine cystinuria: a new classification system. J Vet Intern Med 27:1400-8. [pubmed/24001348]

Henthorn PS, Liu J, Gidalevich T, et al. (2000) Canine cystinuria: polymorphism in the canine SLC3A1 gene and identification of a nonsense mutation in cystinuric Newfoundland dogs. Hum Genet. 107(4):295-303. [pubmed/11129328]

Casal ML, Giger U, Bovee KC, Patterson DF. (1995) Inheritance of cystinuria and renal defect in Newfoundlands. J Am Vet Med Assoc. 207(12):1585-9. [pubmed/493896]