Cerebellar abiotrophy / CA (MUTYH/TOE1 region) - Horse

What does this test analyse?

This genetic test analyses the CA marker in the MUTYH/TOE1 region. The condition is known as cerebellar abiotrophy, CA, cerebellar cortical abiotrophy and sometimes as a form of progressive cerebellar degeneration.

What does it mean for the horse?

In cerebellar abiotrophy, specific nerve cells in the cerebellum do not function normally. Affected foals can develop poor coordination, an unsteady gait, head tremors, exaggerated startle responses and difficulty with controlled movement. The condition is particularly relevant in breeding lines where the CA marker occurs.

The result clarifies whether a horse is clear, carrier or has two copies of the CA marker. This helps breeders plan matings and use carriers responsibly without increasing the risk of affected foals unnecessarily.

Practical value of this test

• Detects the known CA marker in the MUTYH/TOE1 region.
• Distinguishes clear horses, carriers and genetically affected animals.
• Supports breeding selection in Arabians and other lines where CA has been described.
• Helps interpret neurological signs in young horses more precisely.

Inheritance and result

CA is inherited as autosomal recessive. Carriers with one copy are usually clinically healthy but can pass the marker on. Horses with two copies have the CA-risk genotype and can show the condition.