Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to hereditary myopathy with early respiratory failure ?
    ### Response:
    HMERF can be caused by a mutation in the TTN gene. This gene provides instructions for making a protein called titin. Titin plays an important role in muscles the body uses for movement (skeletal muscles) and in heart (cardiac) muscle.  Within muscle cells, titin is an essential component of structures called sarcomeres.
    