Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to benign essential blepharospasm ?
    ### Response:
    The causes of benign essential blepharospasm are unknown, although the disorder likely results from a combination of genetic and environmental factors. Certain genetic changes probably increase the likelihood of developing this condition, and environmental factors may trigger the signs and symptoms in people who are at risk.
    