Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) cleidocranial dysplasia ?
    ### Response:
    Cleidocranial dysplasia is a condition that primarily affects the development of the bones and teeth. Signs and symptoms of cleidocranial dysplasia can vary widely in severity, even within the same family.  Individuals with cleidocranial dysplasia usually have underdeveloped or absent collarbones (clavicles).
    