Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to glucose phosphate isomerase deficiency ?
    ### Response:
    GPI deficiency is caused by mutations in the GPI gene, which provides instructions for making an enzyme called glucose phosphate isomerase (GPI). This enzyme has two distinct functions based on its structure. When two GPI molecules form a complex (a homodimer), the enzyme plays a role in a critical energy-producing process known as glycolysis, also called the glycolytic pathway.
    