Idiopathic dilated cardiomyopathy (IDC) is characterized by dilation and impaired contraction of the left ventricle or both, and it is a relevant cause of heart failure and a common indication for heart transplantation. The major pathogenetic hypothesis in IDC involves autoimmune mediated damage to myocytes. The development of autoimmune inflammatory damage occurs only in patients with a predisposing genetic background. Changes in the immune system concerning cell-mediated and humoral immunity have been detected. The immune system is strictly related to human leukocyte antigen (HLA), which is located on the surface of antigen presenting cells. Its primary function is to restrict T-cell receptors in the process of recognizing auto- or exterior antigen, and thus participates in or mediates immunological recognition, immunological response and immune regulation at various levels. HLA is a genetic marker of susceptibility to autoimmune myocardial damage.1 In the present study, the HLA-DQA1 and -DQB1 alleles in IDC patients were detected with the techniques of polymerase chain reaction-sequence specific primers (PCR-SSP) to explore the immunogenetic mechanisms involved in the pathogenesis of IDC.