Amelogenesis Imperfecta (Samoyed Type) is an inherited dental disorder affecting dogs. Affected dogs have abnormal or badly discolored teeth with irregular tooth surfaces. The deciduous or puppy teeth of these dogs are normal, but abnormalities are apparent upon eruption of the adult teeth. The teeth are often blunted with increased space between teeth due to thinning of the enamel layer. These dogs are predisposed to dental disease and subsequent advanced periodontal disease and bad breath. Tooth loss can occur due to severe abrasions, fractures, and tooth root infections.
Genetic testing of the SCL24A4 gene in will reliably determine whether a dog is a genetic Carrier of Amelogenesis Imperfecta (Samoyed Type). Amelogenesis Imperfecta (Samoyed Type) 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 SCL24A4 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.
Pedersen NC, Shope B, Liu H. An autosomal recessive mutation in SCL24A4 causing enamel hypoplasia in Samoyed and its relationship to breed-wide genetic diversity. Canine Genet Epidemiol. 2017 Nov 22;4:11.