The first axis consists of a series of enzymatic reactions culminating in the generation of angiotensin II (Ang II), which can result in angiotensin II type 1 receptor (AT1R)-dependent MI and cardiac fibrosis by activation of the angiotensin-converting enzyme (ACE)-Ang II-AT1R axis1, 2. The gene discussed is ACE; the disease is myocardial infarction.