A reduction in ACE2 may lead to an increase in ACE activity, which could result in elevated blood pressure and an increased risk of cardiovascular disease, while reduced ACE2 in lung has been implicated in the pathogenesis of pulmonary arterial hypertension, via an imbalance in the renin–angiotensin–aldosterone system system.68, 69. This evidence concerns the gene ACE2 and pulmonary arterial hypertension.