Degenerative Myelopathy Research

Ongoing and Additional Research

As explained in the DM test announcement and the "Using the DNA test" sections of this website, we identified a mutation that can greatly increase a dog’s risk of developing degenerative myelopathy. We have found that dogs with 2 copies of the mutation (testing “affected”) are AT RISK for developing DM at some point in their lives. The age of onset is variable, and there are dogs that test “affected” remain free from symptoms and may die from other causes before ever showing signs of DM. On the other hand, dogs that test “carrier” (one mutant copy and one normal copy) or “clear” (two normal copies) are highly unlikely to develop DM.

We are trying to determine if there are genetic or environmental factors that explain why some dogs that test “affected” develop clincal signs of DM at 8-10 years of age, some are 12-14 or older when symptoms start, and others live into their teens and do not show signs. If genetic or environmental modifiers do exist, we want to identify them. We are also trying to develop therapies that will slow or halt the progression of clinical signs once they start, or perhaps even prevent them from appearing. We expect this ongoing research will yield benefits not only for dogs at risk of developing DM and their owners, but also for people at risk of developing ALS, the human equivalent of DM. The entire research team would like to thank all who have participated in the research so far, and encourage participation from owners and breeders and their veterinarians to assist the ongoing research.

One target of ongoing research is determining why some at risk dogs develop clinical signs relatively early (8-9 yrs of age) and others do not. Researchers at the Broad Institute are searching for possible modifier genes that may influence onset of clinical signs. For this work, we need information and samples from additional dogs. We are offering to DNA test dogs that fit our research criteria at a reduced cost.

DOGS ELIGIBLE FOR A REDUCED FEE DNA TEST:

Dogs must meet the following criteria to be eligible for a reduced cost DNA test:

1) Any dog (any breed, and mixed breed dogs) with a presumptive diagnosis of DM made by your veterinarian or a veterinary neurologist. To locate a neurologist use the "Find a Specialist" link on the ACVIM website - www.ACVIM.org

2) Sample sent is whole, unclotted blood, and our Sample Submission form and DM survey are completed and sent with the sample and fee ($50, payable to University of Missouri)

Samples for reduced cost testing must be sent as blood samples to provide the quality and quantity of DNA needed for the additional research. Please click here to download the instructions and form for sending these samples.

Dogs that do not qualify for the reduced fee DNA test may be tested using the screening test offered by OFA - click here for a link to the online store at OFA where you can order the test.

TISSUE SAMPLES ALSO NEEDED!

We also are continuing to study the pathology of this disease. To do this, we are examining tissues from the nervous system of dogs with DM symptoms, as well as older dogs that do not show any symptoms of DM. When it comes time to have your dog humanely euthanized we would be very grateful for your assistance in obtaining a necropsy (autopsy). We have a protocol that will assist with collection of tissues from specific areas of the nervous system - click here for this protocol.

 

BREEDS AT RISK for Degenerative Myelopathy

As part of this research, we have been surveying many breeds for the presence of the newly discovered mutation. Thru April 2012, we have found the mutation present in over 115 breeds, representing all sizes and types of breeds, as well as mixed breed dogs. Some of these breeds have been previously reported with individuals diagnosed with DM and others have not. We are VERY interested in blood samples and spinal cord samples from presumptively diagnosed dogs of ANY BREED, so that we can confirm the presence of the disease using all useful diagnostic methods.

Now, nearly 4 years after announcing the discovery of the mutation and making DNA testing available, spinal cord sections have been examined from individuals representing over 20 breeds and mixed breed dogs. DM has been confirmed in this wide variety of breeds and mixes. We continue to recruit samples from additional dogs, especially from breeds where we have not previously had the opportunity to examine cords.