Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to chordoma ?
    ### Response:
    Changes in the T gene have been associated with chordoma. An inherited duplication of the T gene identified in a few families is associated with an increased risk of developing a chordoma. Duplications or increases in activity (expression) of the T gene have also been identified in people with chordoma who have no history of the disorder in their family.
    