**4.7 Activating mutations of the mineralocorticoid receptor**

In a family with familial hypertension, hypokalemia and suppressed aldosterone levels, heterozygous mutations were identified in the NR3C2 gene encoding the mineralocorticoid receptor (MR), resulting in a gain of function (Geller, et al., 2000). Additionally, the specificity of the MR was altered such that progesterone was able to bind to it and activate it. Thus pregnant females in this family presented with severe hypertension.
