What are the genetic changes related to myoclonus-dystonia ?
Mutations in the SGCE gene cause myoclonus-dystonia. The SGCE gene provides instructions for making a protein called epsilon ()-sarcoglycan, whose function is unknown. The -sarcoglycan protein is located within the cell membranes of many tissues, but it is most abundant in nerve cells (neurons) in the brain and in muscle cells.  SGCE gene mutations that cause myoclonus-dystonia result in a shortage of -sarcoglycan protein. The protein shortage seems to affect the regions of the brain involved in coordinating movements (the cerebellum) and controlling movements (the basal ganglia). Thus, the movement problems experienced by people with myoclonus-dystonia are caused by dysfunction in the brain, not the muscles. People with this condition show no signs of muscle disease. It is unknown why SGCE gene mutations seem only to affect the brain.