Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Klippel Feil syndrome ?
    ### Response:
    What causes Klippel Feil syndrome (KFS)?  The specific underlying causes and mechanisms of Klippel Feil syndrome (KFS)are not well understood.  In general medical researchers believe KFS happens when the tissue of the embroyo that normally develops into separate vertebrae does not divide correctly.
    