Spinal Dysraphism (SD) in Weimaraners

Quick Summary

Spinal dysraphism (SD) in Weimaraner dogs is a genetic disorder present at birth that results from faulty embryonic development, leading to an abnormal gait as well as weakness and lack of coordination in the rear legs.

Phenotype: Affected Weimaraners have a defective spinal canal, which leads to neurological abnormalities. Puppies born with SD may have difficulties starting to walk due to weakness of their rear legs. Adults with SD show a typical abnormal gait that includes simultaneous movement of the hind legs or “bunny hopping” in the rear. Additional characteristics include weakness and lack of coordination in the rear, together with normal front end coordination and strength. Rarely a “bunny hopping” gait is observed in the front. The condition is not painful, and it does not progress during the life of an affected dog.

Mode of Inheritance: Autosomal recessive

Alleles: N = Normal, SD = Spinal dysraphism

Breeds appropriate for testing: Weimaraner

Explanation of Results:

  • Dogs with N/N genotype will not have spinal dysraphism and cannot transmit this variant to their offspring.
  • Dogs with N/SD genotype will not be affected by spinal dysraphism, but are carriers. They may transmit this variant to 50% of their offspring. Matings between two carriers are predicted to produce 25% spinal dysraphism-affected puppies.
  • Dogs with SD/SD genotype will have spinal dysraphism, a non-progressing condition with neurological abnormalities.

Results of this test can be submitted to the OFA (Orthopedic Foundation for Animals)

Price

$50 one test per animal
$30 as additional test (same animal)

Due to the limitations of current testing methods, the option to add an SD test to an existing sample is not available in the "Add Test to Existing Sample" feature of your MyVGL account. If the SD test was not ordered with the initial sample submission, a new sample must be submitted, and a fee of $50 for the SD test applies to the new sample.

Panels Available
Additional Details

Spinal dysraphism (SD) in Weimaraner dogs is a genetic disorder present at birth that results from faulty embryonic development. Affected Weimaraners have a defective spinal canal which leads to neurological abnormalities. Puppies born with SD may have difficulties starting to walk due to weakness of their rear legs. Adults with SD show a typical abnormal gait that includes simultaneous movement of the hind legs or “bunny hopping” in the rear. Additional characteristics include weakness and lack of coordination in the rear, together with normal front end coordination and strength. Rarely a “bunny hopping” gait is observed in the front. The condition is not painful and it does not progress during the life of an affected dog.

SD is an inherited autosomal recessive disease caused by a mutation in the NKX2-8 gene. Two copies of the mutation are necessary for disease signs to be present, with both sexes being affected equally in frequency and severity. Weimaraners that have only one copy of the SD mutation (N/SD genotype) are normal, but they are carriers of the disease. When two carriers are bred to each other, 25% of the resulting puppies are expected to be affected and 50% to be carriers. Approximately 1.4% of Weimaraners are estimated to be carriers of SD (N/SD); however, the number of carriers can change with each generation. Weimaraners that are carriers of SD (N/SD) are completely normal, and they can be safely bred to dogs that are non-carriers (N/N) in order to maintain diversity within the breed and to select for other positive attributes in carrier dogs.

Testing for SD assists Weimaraner owners and breeders in identifying affected and carrier dogs. Breeders can use results from the test as a tool for selection of mating pairs to avoid producing affected dogs.

 

Note: The Weimaraner spinal dysraphism (SD) test requires specialized DNA extraction and testing methods that are not compatible with methods used for other dog genetic tests. For this reason, the option to add SD is not available in the "Add Test to Existing Sample" feature of your MyVGL account. If SD was not ordered with the initial sample submission, and you wish to add it as a test later, a new sample must be submitted for SD testing.

A fee of $50 for the SD test applies to the new sample.

The VGL is working on a new testing procedure that will allow SD to be added to existing samples, and this will be available once validated.

Turnaround Time
3-6 business days

Species

Dog

Breed

Type of Test

Results Reported As
Test Result Spinal Dysraphism

N/N

No copies of SD mutation. Dog is normal.

N/SD

1 copy of SD mutation. Dog is normal but is a carrier.

SD/SD

2 copies of SD mutation. Dog is affected.

References

Safra, N., Bassuk, A.G., Ferguson, P.J., Aguilar, M., Coulson, R.L., Thomas, N., Hitchens, P.L., Dickinson, P.J., Vernau, K.M., Wolf, Z.T., & Bannasch, D.L. (2013). Genome-wide association mapping in dogs enables identification of the homeobox gene, NKX2-8, as a genetic component of neural tube defects in humans. PLoS Genetics, 9(7):e1003646. doi: 10.1371/journal.pgen.1003646