HSP90AA1 and familial dilated cardiomyopathy: Among these, the SOD2, which is thought to play a role in resisting external superoxide stress, acid tolerance and acid-adaptive response, has been associated with various diseases, including DCM, sporadic motor neuron disease and cancer[28–32], while an increase in the HSP90AA1 activity may represent a response to ischemia and reperfusion injury[33], for example.