Distinct from other cardiomyopathies, CCC displays a helper T-cell type 1 (Th1-T) cell–rich myocarditis with abundant interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) and selectively lower levels of mitochondrial energy metabolism enzymes and high-energy phosphates in the heart. Here, IFNG is linked to cardiomyopathy.