X-linked Ectodermal Dysplasia (X-ED Dog)
X-linked ectodermal dysplasia (X-ED) is an X-linked recessive hereditary disease. It is caused by malformations (dysplasia) of the ectoderm (the outer germ layer of the embryo) and manifests itself, for example, in malformations of hair, teeth and skin.
It occurs in the German Shepherd Dog and the White Shepherd Dog.
Synonym: anhidrotic ectodermal dysplasia
Symptoms
- Missing hair on head and back
- Nasal discharge
- Breathing problems
- Missing or abnormally shaped teeth
General Information
- X-linked ectodermal dysplasia (X-ED) is an X-linked recessive hereditary disease.
- The symptoms are caused by malformations (dysplasia) of the ectoderm (outer germ layer), that is for example malformations of hair, teeth and skin.
- The disease strongly affects the health and quality of life of the dog.
Breeds affected
German Shepherd Dog and White Shepherd Dog
Test Information
This mutation test detects a change of a single base pair (c.910-1G>A) in intron 8 of the EDA gene.
Genotype and Lab Report
Inheritance: X-linked recessive
The affected gene (EDA) is located on the X chromosome. Males with this mutation are affected (X-ed/Y). Females are affected if both X chromosomes are mutated (X-ed/X-ed). They can also have one normal and one mutated chromosome and thus be asymptomatic carriers (X/X-ed).
Genotypes:
X/X
The dog is a healthy female.
X/X-ed
The dog is a carrier female. She is healthy, but can pass the mutation (X-ed) on to 50% of the offspring.
X-ed/X-ed
The dog is an affected female and passes the mutation on to 100% of the offspring, if she is able to reproduce.
X/Y
The dog is a healthy male.
X-ed/Y
The dog is an affected male. If he reaches reproductive age, he could be mated with a healthy female. All "daughters" are carrier females (X/X-ed) and all "sons" are healthy (X/Y).
Recommendations
- Carrier females should not be used for breeding.
- Female offspring of a carrier female should be tested for their genotype (X/X or X/X-ED).
- Affected males (X-ED/Y) should only be mated with healthy females. All female offspring must be tested for their genotype (X/X or X/X-ED).
- In general, breeding with affected animals should be avoided.
Literature
Casal, ML., Scheidt, JL., Rhodes, JL., Henthorn, PS., Werner, P.: Mutation identification in a canine model of X-linked ectodermal dysplasia.Mamm Genome 16:524-31, 2005. Pubmed reference: 16151697. DOI: 10.1007/s00335-004-2463-4
Further information is available at Online Mendelian Inheritance in Animals.