SOD2 and dilated cardiomyopathy: This substrain of C57BL6/J mice shows an increased sensitivity to O2·−/ H2O2, particularly in the absence of mitochondrial MnSOD (SOD2) and a deficiency in both antioxidants results in death within 1–2 days (Huang et al. 2006) due to dilated cardiomyopathy.