Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Harlequin ichthyosis ?
    ### Response:
    What causes harlequin ichthyosis? Harlequin ichthyosis is caused by mutations in the ABCA12 gene. This gene provides instructions for making a protein that is essential for the normal development of skin cells. This protein plays a major role in the transport of fats (lipids) in the outermost layer of skin (the epidermis).
    