Demetz syndrome / Axonopathy / AX (MFN2-related) - Cattle

Demetz syndrome and axonopathy in cattle

This DNA test examines the MFN2 variant c.2229C>T that causes Demetz syndrome. The condition is also known as axonopathy, degenerative axonopathy or AX. It is a severe neurological disorder in which nerve fibres are progressively damaged.

What is seen in affected calves?

• Ataxia: loss of coordination is often the main sign.
• Hindlimb problems: abnormalities are usually most evident in the hind legs, with a wide stance and easy loss of balance.
• Progressive course: signs often begin around one month of age and affected animals eventually lose the ability to stand.

Practical value of this test

The result helps breeders of Tyrol Grey, Tiroler Grauvieh and Blanco Orejinegro cattle distinguish clear animals, carriers and genetically affected animals. Because carriers can be clinically healthy, DNA testing is important for targeted management of the recessive variant and avoidance of carrier pairings.