Ectodermal Dysplasia (ED Dog)

• Extremely thin and fragile skin
• Skin lesions and blistering on contact
• Spontaneous sloughing of the nose and footpad epithelium

• Ectodermal dysplasia (ED) is a skin disease caused by a mutation in the coding gene for Plakophilin 1, a protein of the cytoskeleton.
• The lesions cause a severe reduction in the quality of life.
• Puppies with this disease are usually euthanised immediately after birth.

This mutation test detects a change in a single base pair (c.202+1G>C) in intron 1 of the PKP1 gene.

Inheritance: autosomal recessive

→ The disease only occurs if both alleles of the gene are affected by the mutation (ed/ed). Dogs that have only one allele with the mutation (N/ed) are clinically healthy carriers.

Genotypes:

N/N = genetically normal

The dog has no variant for ED and therefore cannot pass it on to offspring.

N/ed = a carrier

The dog is a clinically healthy carrier. 50% of the variation is passed on to the offspring, who are also carriers.

ed/ed = affected

The variation would be passed on 100% to the offspring, the animals usually do not reach breeding maturity.

• Carrier animals can be bred to normal animals (N/ed x N/N). Before using the offspring in breeding, it should be tested whether they are normal or carriers.
• Mating two carrier animals (N/ed x N/ed) should be avoided because there is a 25% chance that the offspring will be affected.
• Affected animals (ed/ed) should be excluded from breeding, but usually do not reach breeding maturity.

Olivry, T., Linder, K.E., Wang, P., Bizikova, P., Bernstein, J.A., Dunston, S.M., Paps, J.S., Casal, M.L.: Deficient plakophilin-1 expression due to a mutation in PKP1 causes ectodermal dysplasia-skin fragility syndrome in Chesapeake Bay retriever dogs. PLoS One 7:e32072, 2012. Pubmed reference: 22384142. Doi: 10.1371/journal.pone.0032072.

Further information is available at: Online Mendelian Inheritance in Animals.