We previously showed that the pharmaceutical inhibitor Daidzin prevented vascular SMC phenotype switch and significantly reduced the incidence of aortic aneurysm and dissection.[2] As the effect of Daidzin is not cell type‐specific, we combined data from ALDH2−/− mice, ALDH2−/−ApoE−/− mice, ALDH2ECKOPCSK9OE mice and ALDH2EC‐KDApoE−/− mice to confirm the participation of ALDH2 in endothelial cells. The gene discussed is ALDH2; the disease is aortic aneurysm.