VetGen - The leader in veterinary genetic disease research and genetic disease detection services for purebred animals

Breeds Serviced

  • Collie
  • Shetland Sheepdog

Dermatomyositis (DMS)

Dermatomyosits is an inflammatory disease of the skin and muscle. Affected animals develop skin lesions which may last significant amounts of time and muscular atrophy which is most pronounced in the head and neck. The disease is immune-mediated and can be triggered by any number of external factors. A recent study completed by Dr. Leigh Anne Clark at Clemson University has identified mutations which confer susceptibility to this disease in the Collie and Shetland Sheepdog breeds. Our test is based on that work.

While there are three genes involved in susceptibility and we test for all three, testing for only two of them is sufficient to avoid producing potentially affected animals in a breeding program. We test for the Pan2 (A=risk allele, a= non-risk allele) and MAP3K7CL (B=risk allele, b= non-risk allele) mutations described in that research. Testing for both mutations allows placement of dogs into high risk, moderate risk and low risk groupings for likelihood of acquiring DMS. Once you know the result type for these two genes there are very informative charts and breeding tools available by way of the ASSA website (http://americanshetlandsheepdogassociation.org/dermatomyositis/ ).

Result types: The gist of this test is that you want to stay away from producing pups that are homozygous (2 copies) for the risk alleles for either A (Pan2) or B (MAP3K7VCL). The test also includes information on the DLA-DRB1 alleles for each dog.

AABB- high risk for DMS
AABb- high to moderate risk for DMS
AaBB- high to moderate risk for DMS
AAbb- moderate risk for DMS
aaBB- moderate to low risk for DMS

DLA-DRB1 type results

002:01/002:01- two copies of risk allele (CC)
002:01/ other- one copy of risk allele (Cc)
Other/other- zero copies of risk allele (cc)