Graduate Research and Discovery Symposium (GRADS)


Dr. Leigh Anne Clark

Document Type




Publication Date

Spring 2013


Dermatomyositis (DM) is an autoimmune disease of humans and dogs characterized by an inflammatory response in the skin and muscle. In dogs, the predominant clinical sign of DM is small focal areas of scaling and crusting on the face and/or extremities. While there is no cure for DM, symptoms often can be managed with glucocorticoids. DM predominantly affects the collie and Shetland sheepdog breeds, suggesting the involvement of a heritable factor. Identification of the mutation responsible for DM would enable breeders to reduce the incidence of DM in their lines. To identify genomic regions associated with DM, we generated genome-wide SNP profiles for 46 collies using the Illumina CanineHD Infinium BeadChip. A genome-wide association study comparing 26 DM affected and 20 healthy collies revealed numerous significant SNPs near the centromeric end of chromosome 10 (Praw value >= 3.03 x10-9). Evaluation of SNP genotypes revealed a 10.5 Mb haplotype shared by all affected collies. An across-breed approach utilizing genotypes from DM affected Shetland sheepdogs will be used to refine the large candidate region. Simultaneously, positional genes known to have a role in immune response are being investigated for casual variants.