CYP11B2 and hyperaldosteronism: Glucocorticoid remediable aldosteronism (GRA), also known as familial hyperaldosteronism type 1 (FH-I), is a result of the chimeric CYP11B1/CYP11B2 gene, which causes an ectopic expression of aldosterone synthase activity under the regulation of ACTH, resulting in hyperaldosteronism.