Osteogenesis Imperfecta (OI)

Osteogenesis imperfecta (OI) is a hereditary autosomal recessive disease characterized by extremely fragile bones and teeth. Clinical signs include pain, spontaneous fractures of bones and teeth fractures, joint hyperlaxity and reduced bone density on radiography. Teeth are very thin and fragile, otherwise normal size. In affected dogs, clinical signs occur within the first few weeks of life. OI is characterized by significant reduction of the formation of bone and tooth mass (osteopenia and dentinopenia) due to a defect in the formation of collagen type I. Collagen type I represents 90% of the organic material of bones, tendons and teeth. While it gives structure and elasticity to these organs, the defects in collagen lead to fragility.

The reason for the OI occurrence in certain breeds of dogs are mutations in the genes encoding subunits of collagen I. While in Dachshunds, the cause of the OI is the mutation in the gene SERPINH1 involved in the formation of collagen I. The protein encoded by this gene is involved in the correct folding of the collagen triple helix. Defects of the highly organized structure of the collagen triple helix lead to osteogenesis imperfecta.

Inheritance: autosomal recessive

Mutation: SERPINH1 gene

Genetic test: The method used for testing is extremely accurate and allows complete differentiation between affected animals, carriers and healthy dogs. Testing can be done at any age.