UC Davis School of Veterinary Medicine Veterinary Genetics Laboratory

Labrador Retriever Genetic Tests

Centronuclear Myopathy

Introduction

Centronuclear myopathy (CNM) is a naturally occurring, hereditary myopathy of Labrador Retrievers resulting from a mutation in the protein tyrosine phosphatase-like member A gene (PTPLA).  This condition is also known as: type II muscle fiber deficiency, autosomal recessive muscular dystrophy and hereditary myopathy. The disease is inherited in an autosomal recessive fashion with both sexes being equally affected.  CNM typically manifests in puppies at 2-5 months.  Signs of CNM include: generalized loss of muscle tone and control, exercise intolerance and an awkward gait. Dogs with one normal copy and one mutant copy of the gene do not display signs.  Breeding two carriers is predicted to produce 25% affected offspring and 50% carriers of the disease.

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

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

Results reported as:

N/N Normal- no copies of CNM mutation
N/CNM Carrier- 1 copy of CNM mutation; dog is normal. Breedings between carriers are expected to produce 25% affected puppies.
CNM/CNM Affected- 2 copies of CNM mutation

This test is specific for the CNM mutation described in Labrador Retrievers.

Reference:

Pelé M, L. Tiret, JL Kessler, S Blot, JJ Panthier. 2005. SINE exonic insertion in the PTPLA gene leads to multiple splicing defects and segregates with the autosomal recessive centronuclear myopathy in dogs. Human Molecular Genetics 14(11):1417-1427.

Maurer M, J Mary, L Guillaud et al. 2012. Centronuclear myopathy in Labrador Retrievers: A recent founder mutation in the PTPLA gene has rapidly disseminated worldwide. Plos One 7(10): e46408.

Canine Hyperuricosuria
Introduction

Hyperuricosuria (HUU)means elevated levels of uric acid in the urine. This trait predisposes dogs to form 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 but is most commonly found in the Dalmatian, Bulldog and Black Russian Terrier.  Dalmatians are considered to be homozygous for hyperuricosuria. A mutation in exon 5 of the gene Solute carrier family 2, member 9 (SLC2A9) has been found to be associated with hyperuricosuria in dogs.  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.

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

Detailed Hyperuricosuria Information

The VGL offers a DNA test for hyperuricosuria to assist owners and breeders in identifying affected and carrier dogs. The test uses DNA collected from buccal swabs thus avoiding invasive blood collection. Breeders can use results from the test as a tool for selection of mating pairs to avoid producing affected dogs. The test is offered to all breeds, including American Pitbull Terrier, American Staffordshire Terrier, Australian Shepherd, Black Russian Terrier, Bulldog, Dalmatian, German Shepherd, Giant Schnauzer, Jack Russel/Parsons Terrier, Labrador Retriever, Large Munsterlander, South African Boerboel, Vizsla and Weimaraner.

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

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 hyperurisosuria 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.

Research Hyperuricosuria is ongoing to determine other breeds with this problem.  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.

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.

 

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