Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Cornelia de Lange syndrome ?
    ### Response:
    What causes Cornelia de Lange syndrome? Most cases (approximately 65%) of Cornelia de Lange syndrome (CdLS) are caused by changes (mutations) in the NIPBL gene. An additional 5% of people affected by the condition have mutations in one of four known genes (SMC1A, SMC3, HDAC8 and RAD21).
    