Osteogenesis imperfecta (OI) is a genetic problem that affects the bones. The most common effect is weakened bones that break easily. There are at least eight types of OI. Some are mild with no obvious signs, while others are more severe.

The Bones of the Body
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OI is caused by a problem in:

  • The gene that controls the making of collagen—an important element in bones and connective tissues
    • Most common cause of OI.
    • Most often caused by a random change in the gene. Not often associated with a family history.
  • Gene that controls proteins in cartilage
    • Less common cause of OI.
    • An inherited genetic change from parents. There is often a family history.