Mice in which the GR was disrupted by gene-trap integration of a βgeo reporter gene (GRβgeo/+, [39]) displayed a hyperactive HPA with elevated plasma corticosterone and larger adrenal glands due to hyperplasia as well as hypertension due to the activation of the renin–angiotensin–aldosterone system (RAAS) [39]. The gene discussed is REN; the disease is hypertensive disorder.