Test Detail
Familial nephropathy (FN) — Samoyed and English Springer Spaniel
Renal / urinario · Dog
Inherited nephropathy of juvenile onset with progressive glomerulonephritis due to alteration of the glomerular basement membrane (collagen IV). In the Samoyed it is caused by a mutation in COL4A5 (X-linked Alport syndrome); in the English Springer Spaniel the described form is autosomal recessive due to a mutation in COL4A4. It produces proteinuria and progression to renal failure in the young animal.
Incidence
Samoyed: well-characterised X-linked form (Alport model). English Springer Spaniel: less frequent autosomal recessive form. No reliable carrier frequencies are published in large series.
Breeder management
- In the Samoyed, genotype females from affected lines before mating (COL4A5 variant)
- In the Samoyed, a carrier female must not be mated: mating with a clear male produces 50 % carrier daughters and 50 % affected hemizygous sons
- In the Springer, genotype breeding animals with the specific test and do not mate two carriers
- Affected males must not be used as breeding animals
- After a confirmed case, do not repeat the parental mating and communicate the status to the buyer
- In the Samoyed, a carrier female must not be mated: mating with a clear male produces 50 % carrier daughters and 50 % affected hemizygous sons
- In the Springer, genotype breeding animals with the specific test and do not mate two carriers
- Affected males must not be used as breeding animals
- After a confirmed case, do not repeat the parental mating and communicate the status to the buyer
Specialist notes
Differential diagnosis with PLN of the SCWT/Airedale, familial amyloidosis and immune-mediated glomerulonephritis. Renal biopsy shows laminated glomerular basement membrane (Alport syndrome) in the Samoyed; in the Springer, the pattern is that of progressive glomerulonephritis. Determining the inheritance pattern (X-linked Samoyed versus autosomal Springer) is essential for genetic counselling.
References
1. Zheng K et al. (1994) Canine X chromosome-linked hereditary nephritis: a genetic model for human X-linked hereditary nephritis resulting from a single base mutation in the gene encoding the alpha 5 chain of collagen type IV. Proc Natl Acad Sci USA 91(9):3989-3993. PMID: 8171024
2. Nowend KL et al. (2012) Characterization of the genetic basis for autosomal recessive hereditary nephropathy in the English Springer Spaniel. J Vet Intern Med 26(2):294-301. PMID: 22369189
3. OMIA:001112-9615 (Nephritis, X-linked) y OMIA:002618-9615 (Nephropathy, COL4A4 related).
2. Nowend KL et al. (2012) Characterization of the genetic basis for autosomal recessive hereditary nephropathy in the English Springer Spaniel. J Vet Intern Med 26(2):294-301. PMID: 22369189
3. OMIA:001112-9615 (Nephritis, X-linked) y OMIA:002618-9615 (Nephropathy, COL4A4 related).