Dental Hypomineralization

Common Symptoms

Dental Hypomineralization is an inherited developmental tooth disease affecting border collies. Affected dogs have inadequate mineralization of teeth resulting in brittle, light to dark brown teeth which are prone to cracking and severe, premature wear of the chewing surfaces. Over time, excessive wear of tooth enamel often results in exposure of inner tooth pulp causing severe pain and inflammation as well as increasing risk of oral infection and irreparable damage to teeth.

Breed-Specific Information for the Border Collie

The Mutation of the FAM20C gene associated with dental Hypomineralization has been identified in border collies. Though the exact frequency in the overall border collie population is unknown, approximately 11% out of 182 border collies tested were carriers of the mutation.

Testing Tips

Genetic testing of the FAM20C gene in border collies will reliably determine whether a dog is a genetic Carrier of dental Hypomineralization. Dental hypomineralization 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 FAM20C 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. Border collies 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.

References

• Hytonen MK, Arumilli M, Lappalainen AK, Owczarek-Lipska, Jagannathan V, Hundi S, Salmela E, Venta P, Sarkiala E, Jokinen T, Gorgas D, Kere J, Nieminen P, Drogemuller C, Lohi H. Molecular Characterization of Three Canine Models of Human Rare Bone Diseases: Caffey, van den Ende-Gupta, and Raine Syndromes. PLoS Genet. 2016 May 17;12(5):e1006037. doi: 10.1371/journal.pgen.1006037. [PubMed: 27187611]