Oculoskeletal dysplasia Samoyed type
Oculoskeletal dysplasia Samoyed type is a hereditary disorder affecting the Samoyed dog breed. Retinal Dysplasia (RD), is observed in many dog breeds without any pathological consequence. However in the Labrador Retriever breed as well as in Samoyeds, Retinal Folds can be associated with a more severe syndrom, the Oculoskeletal Dysplasia (OSD). Affected dogs exhibit short-limbed dwarfism together with severe ocular defects including vitreous dysplasia, retinal detachment and cataracts, and this phenotype is inherited as an autosomal recessive trait in both breeds. Obligate heterozygotes may exhibit a mild ocular phenotype that ranges from vitreal strands and or localized retinal dysplasia characterized by focal or multifocal retinal folds, to large plaques of dysplastic retinal tissue, but have a normal appendicular skeleton.
Dogs homozygous for either mutation can usually be recognized upon physical examination by an experienced veterinarian, particularly an experienced veterinary ophthalmologist, or an experienced veterinary orthopedist, and sometimes by experienced dog breeders. However, recognition of affected dogs is not sufficient to allow adequate selection pressure to be applied to significantly reduce the gene frequency of the mutation in the population.
Goldstein, O., Guyon, R., Kukekova, A., Kuznetsova, T.N., Pearce-Kelling, S.E., Johnson, J., Aguirre, G.D., and Acland, G.M. (2010). COL9A2 and COL9A3 mutations in canine autosomal recessive oculoskeletal dysplasia. Mamm. Genome 21, 398–408.