T‐type calcium channel‐deficient mice (Cav3.1−/−, Cav3.2−/−) develop less age‐dependent endothelial dysfunction (Thuesen et al., 2018), suggesting that T‐type channels play an important role in age‐induced endothelial dysfunction even though the ageing T‐type deficient mice remained normotensive. The gene discussed is CACNA1G; the disease is endothelial dysfunction.