Interestingly, PDHA1, VDAC2, ACADM, ACADVL, ACAT1, ECH1, CKMT2, MYL2, MYOZ2, TNNT2, and TPM1 expressions were upregulated in DCM and idiopathic dilated cardiomyopathy patients, while A2M, APCS, C3, SERPINA1, GSTM2, GSTM3, PRDX1, PRDX6, GPX3, NPPA, and APOA1 expressions were downregulated in DCM and idiopathic dilated cardiomyopathy patients. The gene discussed is C3; the disease is idiopathic dilated cardiomyopathy.