According to results of the reviews of MI diagnostic criteria conducted in 2012 and 2018 by the European Society of Cardiology (ESC), the American College of Cardiology (ACC), the American Heart Association (AHA) and the World Heart Federation (WHF), the diagnosis verification is based on the presence of myocardial ischemia symptoms (clinical, electrocardiographic, echocardiographic, angiographic) and the positive dynamics of cardiospecific Tn levels in blood of patients (Thygesen et al., 2012; Thygesen et al., 2018; Eckner et al., 2020). The gene discussed is TNC; the disease is myocardial infarction.