Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to Aicardi syndrome ?
    ### Response:
    The cause of Aicardi syndrome is unknown. Because it occurs almost exclusively in females, researchers believe that it is probably the result of a mutation in a gene on the X chromosome. People normally have 46 chromosomes in each cell. Two of the 46 chromosomes, known as X and Y, are called sex chromosomes because they help determine whether a person will develop male or female sex characteristics.
    