Oculoskeletal dysplasia / retinal dysplasia (COL9A3 c.700C>T) - Northern Inuit Dog

What does this test examine?

This genetic test analyses the COL9A3 c.700C>T variant in Northern Inuit Dog and Tamaskan. The condition is also described as oculoskeletal dysplasia, OSD, retinal dysplasia, RD and dwarfism with retinal dysplasia. The result shows whether the dog carries zero, one or two copies of the tested variant.

What does this condition mean?

OSD combines abnormal skeletal development with eye abnormalities. Affected dogs can develop short limbs, abnormal bone growth, joint problems and ocular changes such as retinal dysplasia, retinal detachment, cataracts and reduced vision. The COL9A3 gene encodes type IX collagen, which is important for cartilage, vitreous and retinal structures.

Inheritance and result

The main skeletal form is inherited autosomal recessively. A dog with two copies of the variant is considered genetically affected. Carriers have one copy and can pass the variant on; in OSD1, carriers may sometimes show mild ocular changes.

Practical value of this test

• helps breeders identify carriers before planning a mating
• reduces the risk of producing affected puppies
• adds genetic clarity when dwarfism, retinal dysplasia or early eye changes are present
• supports clear communication with puppy buyers and veterinarians about risk and breeding plans