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Collie Eye Anomaly (CEA)

Collie Eye Anomaly (CEA)

Choroidal Hypoplasia, CH

Collie Eye Anomaly (CEA) is an inherited disease that affects several dog breeds. It can also be referred to as Choroidal Hypoplasia (CH) due to the fact that the choroid layer of tissue is thinner in dogs suffering from the disease. This layer of tissue is responsible for supplying nutrients and blood to the retina. With insufficient blood flow, the choroid does not develop properly and can often lead to retinal detachment and subsequent blindness. The disease can present itself in both a mild and severe form with symptoms varying between affected dogs. Dogs with a mild form of the disease can show thinning of the choroid and may maintain normal vision. Dogs with a more severe version of the disease can have additional eye problems leading to significant vision loss and potentially complete blindness. Although both mild and severe forms of CEA are associated with the same mutation in the NHEJ1 gene, predicting disease severity is difficult.

Reading Your Results


These dogs have two copies of the normal gene and will neither develop CEA nor pass this mutation to their offspring.


These dogs have one copy of the normal gene and one copy of the mutation associated with this disease. They will not develop CEA and will, if bred, pass the mutation to 50% of its offspring, on average.


These dogs have two copies of the mutation associated with CEA which can result in a range of symptoms from vision impairment to complete blindness.

Additional Details


Autosomal Recessive

Affected gene



Ch. 37


7.8 Kb Deletion


Parker HG, Kukekova AV, Akey DT, Goldstein O, Kirkness EF, Baysac KC, Mosher DS, Aguirre GD, Acland GM, Ostrander EA. Breed relationships facilitate fine-mapping studies: a 7.8-kb deletion cosegregates with Collie eye anomaly across multiple dog breeds. Genome Res. 2007 Nov; 17(11):1562-71. [PubMed: 17916641]