Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Glanzmann thrombasthenia ?
    ### Response:
    Glanzmann thrombasthenia (GT) is a rare inherited blood clotting disorder that is present at birth. It is characterized by the impaired function of specialized blood cells, called platelets, that are essential for proper blood clotting. Signs and symptoms vary greatly from person to person.
    