POMC and Aarskog-Scott syndrome, X-linked: Familial glucocorticoid deficiency (FGD) (OMIM #202200), also known as isolated glucocorticoid deficiency, or hereditary unresponsiveness to adrenocorticotropin hormone (ACTH), is an autosomal recessive disorder due to a failure of the action of ACTH to stimulate the adrenal gland to produce glucocorticoids [1].