Dry eye curly coat syndrome is an inherited disease that affects the eyes, skin, and feet of dogs. Affected dogs are usually diagnosed between 2-10 weeks of age with keratoconjuncitivits sicca and ichthyosiform dermatosis. Keratoconjunctivitis sicca, commonly called “dry eye”, is the result of abnormal tear production. Affected dogs often have mucoid, green discharge around their eyes and can develop severe corneal ulcers. Ichthyosiform dermatosis in affected Cavalier King Charles Spaniels is characterized by frizzy sparse hair, dry flakey skin, thickened foot pads, and malformed nails. The skin on the footpads and nails can slough and make standing and walking painful for affected dogs. Affected dogs are also predisposed to dental disease.
Genetic testing of the FAM83H gene will reliably determine whether a dog is a genetic Carrier of dry eye curly coat syndrome. Dry eye curly coat syndrome is inherited in an Autosomal Recessive manner in dogs meaning that they must receive two copies of the mutated gene (one from each parent) to develop the disease. In general, carrier dogs do not have features of the disease but when bred with another carrier of the same Mutation, there is a risk of having affected pups. Each pup that is born to this pairing has a 25% chance of inheriting the disease and a 50% chance of inheriting one copy and being a carrier of the FAM83H gene mutation. Reliable genetic testing is important for determining breeding practices. In order to eliminate this mutation from breeding lines and to avoid the potential of producing affected pups, breeding of known carriers to each other is not recommended. Dogs that are not carriers of the mutation have no increased risk of having affected pups.
There may be other causes of this condition in dogs and a normal result does not exclude a different mutation in this gene or any other gene that may result in a similar genetic disease or trait.
Barnett KC. Congenital keratoconjunctivitis sicca and ichthyosiform dermatosis in the cavalier King Charles spaniel. J Small Anim Pract. 2006 Sep;47(9):524-8.
Hartley C, Donaldson D, Smith KC, Henley W, Lewis TW, Blott S, Mellersh C, Barnett KC. Congenital keratoconjunctivitis sicca and ichthyosiform dermatosis in 25 Cavalier King Charles spaniel dogs - Part I: clinical signs, histopathology, and inheritance. Vet Ophthalmol. 2012 Sep;15(5):315-26.