Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to glycogen storage disease type IV ?
    ### Response:
    Mutations in the GBE1 gene cause GSD IV. The GBE1 gene provides instructions for making the glycogen branching enzyme. This enzyme is involved in the production of glycogen, which is a major source of stored energy in the body. GBE1 gene mutations that cause GSD IV lead to a shortage (deficiency) of the glycogen branching enzyme.
    