title: Degenerative myelopathy in German Shepherd Dog: comparison of two molecular assays for the identification of the SOD1:c.118G>A mutation.
abstract: Degenerative myelopathy (DM) is a late-onset, slowly progressive degeneration of spinal cord white matter which is reported primarily in large breed dogs. The missense mutation SOD1:c.118G>A is associated with this pathology in several dog breeds, including the German Shepherd Dog (GSD). The aims of the present study were to develop a tool for the rapid screening of the SOD1 mutation site in dogs and to evaluate the association of the polymorphism with DM in the German Shepherd breed. Two different techniques were compared: a minisequencing test and a real-time pcr allelic discrimination assay. Both approaches resulted effective and efficient. A sample of 47 dogs were examined. Ten subjects presented the symptoms of the illness; for one of them the diagnosis was confirmed by postmortem investigations and it resulted to be an A/A homozygote. In another clinically suspected dog, heterozygote A/G, the histopathological examination of the medulla showed moderate axon and myelin degenerative changes. GSD shows a frequency of the mutant allele equal to 0.17, quite high being a high-risk allele. Because canine DM has a late onset in adulthood and homozygous mutant dogs are likely as fertile as other genotypes, the natural selection is mild and the mutant allele may reach high frequencies. A diagnostic test, easy to implement, may contribute to control the gene diffusion in populations. The SOD1:c.118G>A mutation could be a useful marker for breeding strategies intending to reduce the incidence of DM.
authors.affiliation: Department of Veterinary Sciences, University of Turin, via Leonardo da Vinci, 44, 10095, Grugliasco, Italy.
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Capucchio
authors.forename: Veronica
authors.initials: V
authors.lastname: Spalenza
authors.forename: Elena
authors.initials: E
authors.lastname: Biasibetti
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Bottero
authors.forename: Roberto
authors.initials: R
authors.lastname: Rasero
authors.forename: Alessandra
authors.initials: A
authors.lastname: Dalmasso
authors.forename: Paola
authors.initials: P
authors.lastname: Sacchi
mesh_terms: D000818:Animals; D004283:Dog Diseases / Q000235:genetics; D004285:Dogs; D005260:Female; D008297:Male; D020125:Mutation, Missense; D019636:Neurodegenerative Diseases / Q000235:genetics* / Q000662:veterinary; D011110:Polymorphism, Genetic; D013116:Spinal Cord / Q000473:pathology; D013118:Spinal Cord Diseases / Q000235:genetics* / Q000473:pathology; D013482:Superoxide Dismutase / Q000235:genetics*; D000072105:Superoxide Dismutase-1
chemical_list: D013482:Superoxide Dismutase; D000072105:Superoxide Dismutase-1