Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) osteogenesis imperfecta ?
    ### Response:
    Osteogenesis imperfecta (OI) is a group of genetic disorders that mainly affect the bones. The term "osteogenesis imperfecta" means imperfect bone formation. People with this condition have bones that break easily, often from mild trauma or with no apparent cause.
    