Dental Hypomineralization

Dental hypomineralization is a hereditary disease in dogs that affects the mineralization process of the teeth and causes them to become brittle and wear easily.

Symptoms

Signs of dental hypomineralization may include teeth that appear translucent or lighter than normal, teeth that break or wear easily, and possibly, inflammation in the tissue surrounding the teeth, pain and discomfort when chewing. In some cases, the teeth may appear normal to the naked eye, but may be more susceptible to decay and wear. When tooth wear is severe, the dental pulp may become exposed.

Disease Management

A complete dental examination should be performed, which may include x-rays to evaluate the inside of the teeth. Treatment may involve correction of any nutrition or infection problems, as well as regular dental care to help protect the teeth.

Genetic basis

This disease follows an autosomal recessive mode of inheritance. Autosomal recessive inheritance means that the dog, regardless of sex, must receive two copies of the mutation or pathogenic variant to be at risk of developing the disease. Both parents of an affected dog must carry at least one copy of the mutation. Animals with only one copy of the mutation are not at increased risk of developing the disease, but may pass the mutation on to future generations. Breeding between dogs carrying genetic variants that can cause disease, even if they do not show symptoms, is not recommended.

Technical report

Dental hypomineralization in border colies is caused by a mutation in the FAM20C gene that has been shown to be related to the process of cell differentiation of odontoblasts (cells that produce dentin), ameloblasts (cells that produce dental enamel), osteoblasts (cells that produce bone matrix) and osteocytes (cells that make up bone tissue) during the development of teeth and bones. Hytönen et al. observed that the disease-causing mutation of FAM20C is c.899C>T. It affects a highly conserved amino acid in the FAM20C protein that is located in the functional kinase domain, so the function of the protein may be altered.

Most affected breeds

Border Collie

Bibliography

Hytönen MK, Arumilli M, Lappalainen AK,et al. 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.