Craniomandibular osteopathy / CMO / Lion Jaw (SLC37A2-related) - Terrier type

What does this test analyse?

This genetic test analyses the SLC37A2 variant c.1332C>T in Cairn Terrier, Scottish Terrier and West Highland White Terrier. The condition is known as craniomandibular osteopathy, CMO, Lion Jaw, Scotty Jaw and Westie Jaw.

What does this mean for the dog?

CMO is a developmental disorder of the skull and jaw bones in young dogs. It is also known as craniomandibular osteopathy, CMO, Lion Jaw, Scotty Jaw and Westie Jaw. Signs often start around four to eight months of age and may include jaw swelling, pain, difficulty eating or opening the mouth, reduced appetite and periodic fever.

Practical value of this test

• Breeders can identify dogs carrying the SLC37A2 variant before planning matings.
• The result helps keep variants with increased CMO risk out of risk matings.
• Because penetrance is incomplete, a dog with the variant may have mild, clear or no visible signs; this makes the breeding value of the test especially important.
• In young terriers with jaw swelling, pain or difficulty eating, the test supports a concrete genetic explanation.
• The test helps distinguish SLC37A2-related CMO from other skull or jaw disorders.

Inheritance and interpretation

The trait is described as autosomal dominant with incomplete penetrance. C/C means the tested variant was not detected. C/T means one copy of the variant is present and the dog carries genetic risk for CMO. T/T means two copies are present; severity may vary because penetrance is incomplete, but this is a genetically high-risk result.