UC Davis School of Veterinary Medicine Veterinary Genetics Laboratory
SERVICES

Weimaraner Genetic Tests

Tests Offered:
HYM | HUU

Hypomyelination in Weimaraner Dogs:

Introduction

Researchers from the University of Wisconsin Madison lead by Dr. Ian Duncan in collaboration with researchers from Dr. Patel’s Laboratory at The University of Southern California and Dr. Bannasch’s Laboratory here at University of California Davis have identified the genetic basis for hypomyelination in the Weimaraner. The manuscript detailing this discovery is in press in the journal GLIA. This condition leads to tremors during puppyhood. The disease is inherited as a simple autosomal recessive disorder and the carrier frequency has been estimated to be 4.29% within the breed.  Hypomyelination is also called ”Tremors” and “Shaking puppies” by dog breeders based on the fact that affected puppies have tremors when awake as early as 2 weeks of age. Clinical signs resolve in most cases by 3-4 months of age. Some of the dogs may have a mild persistent tremor of the hind legs.

Hypomyelination test information:

The VGL offers a DNA test for Hypomyelination to assist owners and breeders in identifying affected and carrier dogs. The test uses DNA collected from buccal swabs thus avoiding blood collection. Breeders can use results from the test as a tool for selection of mating pairs to avoid producing affected dogs.

The following chart details the expected outcomes of matings for all possible combinations of Hypomyelination genotypes.

ORDER TEST KITS | PRICE LIST
Allow 2-6 business days for results.

Female

Male

N/N

N/HYM

HYM/HYM

N/N

100% N/N

50% N/N, 50% N/HYM

100% N/HYM

N/HYM

50% N/N, 50%N/HYM

25% N/N, 50% N/HYM, 25% HYM/HYM

50% N/HYM, 50% HYM/HYM

HYM/HYM

100% N/HYM

50% N/HYM, 50% HYM/HYM

100% HYM/HYM

 

Results reported as:

N/N no copies of hypomyelination mutation; dog is normal
N/HYM 1 copy of hypomyelination mutation; dog is normal but is a carrier
HYM/HYM 2 copies of hypomyelination mutation; dog is affected.

Dogs that have only one mutant copy of HYM (N/HYM) are normal but they are carriers of the disease. When two carriers are bred to each other the resulting puppies can be affected. At the time that this test was released, approximately 4.3% of Weimaraners were carriers of HYM (N/HYM); however, the number of carriers can change with each generation. Dogs that are carriers of HYM (N/HYM) are completely normal and they can be safely bred to dogs that are non-carriers of HYM (N/N) in order to maintain diversity within the breed and to select for other positive attributes in carrier dogs.

References:

Pemberton TJ, Choi S, Mayer JA, Li FY, Gokey N, Svaren J, Safra N, Bannasch DL, Sullivan K, Breuhaus B, Patel PI, Duncan ID. (2013) A mutation in the canine gene encoding folliculin-interacting protein 2 (FNIP2) associated with a unique disruption in spinal cord myelination. Glia 62:39-51.

Hyperuricosuria in Weimaraner Dogs:

Introduction

Researchers in the Bannasch Laboratory have identified the genetic basis of Hyperuricosuria in dogs.  Hyperuricosuria (HUU) means elevated levels of uric acid in the urine. This trait predisposes dogs to form urate stones in their bladders or sometimes kidneys. These stones often must be removed surgically and can be difficult to treat. Hyperuricosuria is inherited as a simple autosomal recessive trait.  The trait can occur in any breed and the carrier frequency within the Weimaraner breed has been estimated to be ~25%.  A DNA test for this specific mutation can determine if dogs are normal or if they carry one or two copies of the mutation. Dogs that carry two copies of the mutation will be affected and susceptible to develop bladder/kidney stones.

HUU test information:

The VGL offers a DNA test for HUU to assist owners and breeders in identifying affected and carrier dogs. The test uses DNA collected from buccal swabs thus avoiding invasive blood collection. We recommend testing any dog that has formed kidney or bladder stones composed of urate or uric acid. If the dog has the mutation then treatment modalities for Dalmatians can be used to treat the dog. Breeders can use results from the test as a tool for selection of mating pairs to avoid producing affected dogs.

The following chart details the expected outcomes of matings for all possible combinations of hyperuricosuria genotypes.

ORDER TEST KITS | PRICE LIST
Allow 2-6 business days for results.

Female

Male

N/N

N/HU

HU/HU

N/N

100% N/N

50% N/N, 50% N/HU

100% N/HU

N/HU

50% N/N, 50% N/HU

25% N/N, 50% N/HU, 25% HU/HU

50% N/HU, 50% HU/HU

HU/HU

100% N/HU

50% N/HU, 50% HU/HU

100% HU/HU

 

Results reported as:

N/N no copies of hyperuricosuria mutation; dog is normal
N/HU 1 copy of hyperuricosuria mutation; dog is normal but is a carrier.
HU/HU 2 copies of hyperuricosuria mutation; dog is affected and susceptible to develop bladder/kidney stones.

Dogs that have only one mutant copy of HUU (N/HU) are normal but they are carriers of the disease. When two carriers are bred to each other the resulting puppies can be affected. At the time that this test was released, approximately 25% of Weimaraners were carriers of HUU (N/HU); however, the number of carriers can change with each generation. Dogs that are carriers of HUU (N/HU) are completely normal and they can be safely bred to dogs that are non-carriers of HUU (N/N) in order to maintain diversity within the breed and to select for other positive attributes in carrier dogs.

References:

Bannasch D, N Safra, A Young, N Karmi, RS Schaible and GV Ling (2008) Mutations in the SLC2A9 gene cause hyperuricosuria and hyperuricemia in the dog. PLoS Genetics 4(11): e1000246. doi:10.1371/journal.pgen.1000246

Karmi N, EA Brown, SS Hughes, B McLaughlin, CS Mellersh, V Biourge, and DL Bannasch (2010) Estimated frequency of the canine hyperuricosuria mutation in different dog breeds. Journal of Veterinary and Internal Medicine 2010;24:1337–1342.

Jodi L. Westropp, EG Johnson, MC Fuller, N Safra, DL Bannasch. Urate urolithiasis and hyperuricosuria in a Weimaraner, secondary to the SLC2A9 transporter defect. (Under review in Veterinary Record).

 
Veterinary Genetics Laboratory, Tel 530-752-2211, Email VGL