What is it?

Osteogenesis imperfecta is a group of genetic disorders that mainly affect the bones. People with OI have bones that fracture (break) easily, often from mild injury or with no clear cause. There are at least 19 recognized forms of OI (types I through XIX).1

What causes it?

Osteogenesis imperfecta can be caused by mutations (changes) in one of several genes. Mutations in the COL1A1 and COL1A2 genes cause approximately 90% of all cases. These genes provide instructions for making proteins that are used to assemble type I collagen, which is the most commonly found protein in bone, skin, and other connective tissues that provide structure and strength to the body.1

What are some of the common symptoms?1

  • Frequent bone fractures
  • Blue/gray tint to the part of the eye that is usually white (sclera)
  • Short stature
  • Curvature of the spine (scoliosis)
  • Joint deformities (contractures)
  • Hearing loss
  • Respiratory (breathing) problems
  • Tooth development disorder (dentinogenesis imperfecta)

How many people have it?

Osteogenesis imperfecta affects an estimated 1 in 10,000 to 20,000 people worldwide and 25,000 to 50,000 people in the United States.1

Common Names for Osteogenesis Imperfecta1

  • OI
  • Brittle bone disease
  • Fragilitas ossium
  • Vrolik disease

1Osteogenesis imperfecta. Nation Institutes of Health: MedlinePlus Website. https://medlineplus.gov/genetics/condition/osteogenesis-imperfecta/. Accessed April 26, 2021.

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