There have been a handful of White Swiss Shepherds imported to the USA and tested via Embark DNA who have been found to be CEA carriers.
A few of these dogs are half siblings through their sire-line, indicating that this one particular line carries the gene. However, in addition there is at least one other dog who is a carrier of CEA and who is not closely related to this line.
As of now, many who are not completing full DNA panels are not testing for CEA, therefore are not aware of their line carries the gene. Perhaps it would be best if breeders began listing CEA results alongside MDR1 (Multi Drug Resistance 1) and DM (Degenerative Myelopathy) results, which are already common genetic tests within the breed.
Without more dogs completing testing for CEA, it is impossible to say how common it is for the gene to appear in the breed. At this point, we are unaware of any dogs who have come back CEA affected (two copies of the gene), but that does not mean that they do not exist.
We have created this post in hopes of starting conversation about CEA and to raise awareness of its existence in White Swiss Shepherds. If you have anything to add, please leave a comment here or on social media.
The above is a screenshot from Embark about Collie Eye Anomaly.