Hence, we first studied the impact of DNA methylation at the LY75, ERBB3, HOXB13, and ADORA2A loci on their gene expression by quantitative PCR (q-PCR) in controls, mild DCM (NYHA class II) and moderate to severe DCM (NYHA class III–IV). This evidence concerns the gene ADORA2A and familial dilated cardiomyopathy.