Centronuclear myopathy type 1 / ADCNM / DNM2-CNM (DNM2-related) - Border Collie

What does this test analyse?

This genetic test analyses the DNM2 c.1393C>T variant in the Border Collie. The disorder is described as centronuclear myopathy type 1, autosomal dominant centronuclear myopathy, ADCNM or DNM2-CNM.

What does this mean for the dog?

DNM2 is involved in normal muscle-cell structure and membrane dynamics. The tested variant changes the protein at R465W and causes an autosomal dominant form of centronuclear myopathy. Affected Border Collies may develop muscle weakness, muscle wasting, exercise intolerance, a bunny-hopping gait, reduced appetite and exercise-induced limb collapse. First signs are often seen around one year of age.

Practical value of this test

• Breeders can identify dogs carrying the dominant DNM2 variant before breeding.
• The result supports targeted breeding selection, mate choice and avoiding transmission to offspring.
• In Border Collies with exercise intolerance, abnormal gait or muscle loss, the test helps confirm DNM2-CNM genetically.
• The test gives clearer sales, breeding and health communication because the exact tested genotype is reported.

Inheritance and result

This variant is autosomal dominant. A dog with C/C does not carry the tested variant. A dog with C/T has one copy of the DNM2 variant; one copy is sufficient to cause DNM2-related centronuclear myopathy. T/T means two copies of the variant and is reported as a positive/affected genotype.