This is important given that changes in Runx1 expression at the mRNA and protein levels are not restricted to rodent MI models but also occur in patients with MI.5,7 In separate experiments, we were able to demonstrate that Runx1 expression is increased within the BZ and infarct region after MI within the contractile elements of the heart—that is, the cardiomyocytes—as early as 1 to 14 days after MI (Figure 1). The gene discussed is RUNX1; the disease is myocardial infarction.