Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the genetic changes related to intranuclear rod myopathy ?
    ### Response:
    Intranuclear rod myopathy is caused by a mutation in the ACTA1 gene. This gene provides instructions for making a protein called skeletal alpha ()-actin, which is part of the actin protein family. Actin proteins are important for cell movement and the tensing of muscle fibers (muscle contraction).
    