HCG was tested as a proof of concept for a single-target assay as well as three myocardial infarction markers comprising cardiac troponin I (cTnI), creatine kinase isoenzyme MB (CKMB), and myohemoglobin (Myo) for a multiplex assay, and satisfactory detection results were obtained. The gene discussed is TNNI3; the disease is myocardial infarction.