Dental Hypomineralization (DH) Raine’s Syndrome

Description

Dental Hypomineralization (DH) is also known as Raine Syndrome. DH is an autosomal recessive disorder that is known to affect Border Collies. This disorder is characterized by extreme wear of the teeth that can be very painful. The only way to treat this condition is by extracting worn teeth.

DH can be a very painful condition. The genetic mutation that causes DH is suspected to be carried by 11% of the Border Collie population. The mutation occurs in the FAM20C gene. This gene codes for a protein that binds together calcium and phosphorylates involved in bone mineralization. Without this protein, normal mineralization of the teeth cannot occur. This means that the teeth are not as strong as they should be and are more vulnerable, leading to excessive wear.  While this condition affects the dog from birth, symptoms may not become noticeable for some time. Typically, symptoms will become noticeable before the dog reaches two years old, however, this can vary depending on the severity. 

A common occurrence in dogs with DH is the browning of the teeth. While many dogs will experience this later in life, dogs with DH develop brown teeth at an early age. Furthermore, a condition known as Pulpitis is commonly associated with DH. Pulpitis is characterized by inflammation of the dental pulp. This is located within the tooth itself. Because of the excessive wear on the tooth, the pulp inside can become exposed and lead to inflammation. Although diagnosis of Pulpitis can be difficult, a telltale sign of Pulpitis is intrinsic tooth discoloration. The tooth appears to be colored pink or purple-grey from within, rather than due to an exterior source. Pulpitis eventually causes tooth death, requiring tooth extraction. 

DH is an autosomal recessive disorder. This means that a dog must inherit two copies of the mutation in order to present symptoms of DH. A dog with one copy of the mutation is known as a carrier and does not present symptoms. If two carriers are bred to one another, there is a 25% chance per puppy born that they will develop symptoms of DH and a 50% chance per puppy born that they will also be carriers of DH. Because DH is technically untreatable, the only way to manage DH is through prevention. Genetic testing can reveal the likelihood of a dog developing DH and can inform a breeder of major health concerns.