Affected gene: COL9A2
Inheritance: Autosomal recessive for dwarfism issues, carrier dogs may have mild eye defects (e.g. retinal folds)
Mutation: Chr15: a 1,267 bp deletion that eliminates part of the 5'UTR, all of exon 1 and part of intron 1
OMIA link: 001523-9615

Appropriate breeds for testing: Samoyed

Symptoms:
Affected dogs exhibit dwarfism of short limbs and eye problems. Symptoms can be visible from 4 to 6 weeks of age and include associated ophthalmic lesions include retinal detachment and cataracts as well as shorter limbs. In general, carrier dogs do not have skeletal abnormalities, but may have ocular defects (eg. retinal folds). Breeding of carrier animals is therefore not recommended.

Reference:
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. 2010 Aug; 21(7-8):398-408