Early Adult Onset Deafness (EAOD) in Border Collies

Early Adult Onset Deafness (EAOD) in Border Collies

EAOD is a genetic condition affecting the hearing of Border Collies. DNA testing is possible for several risk factors associated with the condition, reducing the risk of passing the condition to future generations.

What is Early Adult Onset Deafness (EAOD)?

Many dogs experience some degree of hearing loss as they age, typically beginning around 8 to 10 years old. However, in the case of Early Adult Onset Deafness (EAOD), this hearing loss starts much earlier – between 3 and 5 years of age.

For working Border Collies, this presents a serious issue, as their hearing is essential for performing tasks. Even mild hearing loss can significantly impact their ability to work effectively. Although EAOD does not cause other major health problems, its impact on performance can be profound.

How is EAOD tested?

Several genetic mutations (DNA variants) have been identified that are associated with EAOD. These mutations do not directly cause deafness but are commonly found in dogs affected by EAOD. Each of these variants is considered a risk factor.

CombiBreed tests for the four variants most strongly linked to EAOD, reported as EAOD 1, 2, 3, and 4. For each of these variants, a dog can be classified as clear (normal), carrier or affected.

What does a risk factor mean and who should be concerned?

If a dog is found to be a carrier or affected by one or more EAOD-related variants, it has a higher risk of developing EAOD. While the exact risk associated with each individual variant is still being studied, this information is crucial for making responsible breeding decisions. This is especially important for breeders whose dogs have a family history of deafness, since the correlation betwee the risk factor and the condition is strongest in these dogs. The general recommendation is to only pair carriers or affected dogs with partners that are clear of these variants. Doing so helps reduce the likelihood of deafness in future generations.

My dog is not a Border Collie but is carrier or affected by EAOD, what should I do?

It is possible for non-Border Collies to carry one or more copies of the EAOD-associated risk variants. However, these genetic mutations are only known to be relevant in Border Collies, particularly those with a family history of EAOD. If your dog belongs to a different breed and tests as a carrier or affected for one or more of these EAOD variants, this result has no known clinical significance. There is currently no evidence that these variants cause hearing loss in breeds other than the Border Collie. Therefore, if your dog is not a Border Collie, there is no need to adjust your breeding decisions based on these EAOD test results.

Relevant tests

• H822
• H893
• H850
• H851
• H852