OMIA 001523-9615 : Oculoskeletal dysplasia 2 in Canis lupus familiaris

Possibly relevant human trait(s) and/or gene(s) (MIM number): 614284

Mendelian trait/disorder: yes

Mode of inheritance: Autosomal Recessive

Considered a defect: yes

Key variant known: yes

Year key variant first reported: 2010

Species-specific symbol: osd2; drd2

Species-specific description: Oculoskeletal dysplasia is a collagen disorder characterized by short-limbed dwarfism, particularly of the forelimbs, and vitreous dysplasia with associated retinal detachment and cataracts. A genetic test is available.

History: This disorder was first characterized in the Samoyed by Meyers et al (1983).

Inheritance: Obligate heterozygotes do not have skeletal lesions but may exhibit mild ocular lesions (Goldstein et al., 2010).

Mapping: CFA15

Molecular basis: The causative mutation is a 1,267 bp deletion that eliminates part of the 5’UTR, all of exon 1 and part of intron 1, which likely causes mRNA degradation and absence of COL9A2 protein (Goldstein et al., 2010).

Clinical features: Signs may be noticeable as early as 4 to 6 weeks of age (Goldstein et al., 2010). Affected dogs have short-limbed dwarfism and vitreous dysplasia. Associated ophthalmic lesions include retinal detachment and cataracts. The forelimbs are most noticeably affected, particularly the short radius and ulna, which subsequently develop curvature with varus/valgus deformities (Meyers et al., 1983). In pups, the dome of the cranium is often pronounced and there is moderate excessive exotropic strabismus. Some, but not all, carriers have vitreal stands, focal retinal folds or plaques of retinal dysplasia (Goldstein et al., 2010).

Pathology: There is a range of ocular defects, but the most consistent findings are cortical equatorial cataracts and vitreal liquefaction (Goldstein et al, 2010).

Control: Parents and siblings of affected dogs should be tested. Breeding of affected or carrier dogs is not recommended.

Genetic testing: There is a test available to detect the causative mutation. Dogs cannot be reliably identified by clinical signs alone, so dogs suspected to have oculoskeletal dysplasia should be tested.

Breed: Samoyed.

Associated gene:

Symbol Description Species Chr Location OMIA gene details page Other Links
COL9A2 collagen, type IX, alpha 2 Canis lupus familiaris 15 NC_006597.3 (2615428..2661552) COL9A2 Homologene, Ensembl, NCBI gene


By default, variants are sorted chronologically by year of publication, to provide a historical perspective. Readers can re-sort on any column by clicking on the column header. Click it again to sort in a descending order. To create a multiple-field sort, hold down Shift while clicking on the second, third etc relevant column headers.

WARNING! Inclusion of a variant in this table does not automatically mean that it should be used for DNA testing. Anyone contemplating the use of any of these variants for DNA testing should examine critically the relevant evidence (especially in breeds other than the breed in which the variant was first described). If it is decided to proceed, the location and orientation of the variant sequence should be checked very carefully.

Breed(s) Variant Phenotype Gene Allele Type of Variant Reference Sequence Chr. g. or m. c. or n. p. Verbal Description EVA ID Year Published PubMed ID(s) Acknowledgements
Samoyed Oculoskeletal dysplasia 2 COL9A2 deletion, gross (>20) a 1,267 bp deletion that eliminates part of the 5’UTR, all of exon 1 and part of intron 1 2010 20686772


Note: the references are listed in reverse chronological order (from the most recent year to the earliest year), and alphabetically by first author within a year.
2012 Miyadera, K., Acland, G.M., Aguirre, G.D. :
Genetic and phenotypic variations of inherited retinal diseases in dogs: the power of within- and across-breed studies. Mamm Genome 23:40-61, 2012. Pubmed reference: 22065099. DOI: 10.1007/s00335-011-9361-3.
2010 Goldstein, O., Guyon, R., Kukekova, A., Kuznetsova, TN., Pearce-Kelling, SE., Johnson, J., Aguirre, GD., Acland, GM. :
COL9A2 and COL9A3 mutations in canine autosomal recessive oculoskeletal dysplasia. Mamm Genome 21:398-408, 2010. Pubmed reference: 20686772. DOI: 10.1007/s00335-010-9276-4.
1995 Acland, G.M., Aguirre, G.D. :
Oculoskeletal dysplasias in Samoyed and Labrador retriever dogs: nonallelic disorders akin to Stickler-like syndromes affecting humans 2nd international DOGMAP meeting, Cambridge :, 1995.
1983 Meyers VN, Jezyk PF, Aguirre GD, Patterson DF :
Short-limbed dwarfism and ocular defects in the Samoyed dog. J Am Vet Med Assoc 183:975-979 , 1983. Pubmed reference: 12002589.

Edit History

  • Created by Frank Nicholas on 02 Nov 2010
  • Changed by Vicki Meyers-Wallen on 13 Sep 2011
  • Changed by Frank Nicholas on 28 Sep 2011
  • Changed by Frank Nicholas on 08 Dec 2011
  • Changed by Frank Nicholas on 12 Dec 2011
  • Changed by Frank Nicholas on 15 Oct 2016