Cystinuria, type II-B

Gene: SLC7A9

Transmission: Autosomal dominant

For an autosomal dominant genetic disease, an animal must have at least one copy of the mutation in question to be at risk of developing the disease.  Animals with two copies of the mutation generally have more severe symptoms and an earlier onset of the disease than animals with just one copy of the mutation.  One or both of the parents of an animal with the mutation has one or two copies of the mutation.  Animals that have one or two copies of the mutation can pass the mutation on to future generations.

Mutation : Substitution, SLC7A9 gene; c.964 G>A, p.(G322R), exon9

Medical system: Renal

Breeds: Miniature Pinscher

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: [1880-9615]

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]

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]