Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) GM1 gangliosidosis ?
    ### Response:
    GM1 gangliosidosis is an inherited disorder that progressively destroys nerve cells (neurons) in the brain and spinal cord. Some researchers classify this condition into three major types based on the age at which signs and symptoms first appear. Although the three types differ in severity, their features can overlap significantly.
    