Other Names: Alport Syndrome
Affected Gene: COL4A5
Transmission: X-linked recessive
In X-linked recessive hereditary genetic diseases, the following rules apply:
  
Males are affected (at risk of developing the disease) even if they only have one copy of the mutation.
  
Transmission from male to male does not exist, as a male never passes his X chromosome to his sons.
  
All females of an affected male will inherit the mutant gene.
  
Carrier females have a 50% chance of passing the mutant gene to their sons and daughters.
Mutation: CanFam3.1 X g.82196868G>T c.3079G>T
OMIA Link: 001112-9615

Breeds Recommended for Testing:  Samoyed

Symptoms:
Hereditary nephritis is a kidney disease. Normally, there are no proteins in the urine, but in affected dogs, a defect allows blood proteins to be filtered by the kidneys and lost in the urine. These urinary proteins can be detected as early as 2-3 months of age, and signs of chronic kidney failure (such as thirst, frequent urination, vomiting, loss of appetite, etc.) can appear between 7-15 months. Since the disease is X-linked, males are more commonly affected than females. Female carriers of the mutation may also show signs of kidney disease, but the progression is generally slower. Some females may show no signs of kidney disease. Affected male dogs eventually die from chronic kidney failure at around 15 months of age.
References:
  
Baumal R, Thorner P, Valli VEO, McInnes R, Marrano P, Jacobs R, Binnington A, Bloedow AG. Renal disease in carrier female dogs with X-linked hereditary nephritis.
Am J Pathol. 1991 Oct;139(4):751-64.
  
Jansen B, Valli VE, Thorner P, Baumal R, Lumsden JH. Samoyed glomerulopathy: serial, clinical and laboratory (urine, serum biochemistry and hematology) studies.
Can J Vet Res. 1987 Jul;51(3):387-93.
  
Zheng K, Thorner PS, Marrano P, Baumal R, McInnes RR. 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. 1994 Apr 26;91(9):3989-9.