The inactivating heterozygous mutations of the NR3C1/GR gene are the cause of congenital primary generalized GC resistance or Chrousos ́ syndrome (OMIM #615962), a rare genetic condition characterized by hypercortisolism without signs of Cushing’s syndrome. The gene discussed is NR3C1; the disease is Cushing syndrome due to macronodular adrenal hyperplasia.