Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to autosomal recessive primary microcephaly ?
    ### Response:
    MCPH can result from mutations in at least seven genes. Mutations in the ASPM gene are the most common cause of the disorder, accounting for about half of all cases.  The genes associated with MCPH play important roles in early brain development, particularly in determining brain size.
    