Below is an instruction from Human. Write a response.
    ### Instruction:
    What causes Glucose transporter type 1 deficiency syndrome ?
    ### Response:
    What causes glucose transporter type 1 deficiency syndrome? Glucose transporter type 1 deficiency syndrome (GLUT1 deficiency syndrome) is caused by changes (mutations) in the SLC2A1 gene. This gene encodes a protein that helps transport glucose (a simple sugar) into cells where it is used as fuel.
    