One patient, who was diagnosed with acromegaly with positive immunohistochemical staining for GH, ACTH, PRL, and LH, showed high ACTH (normal laboratory range: 3–66 pg/mL) and cortisol levels (normal laboratory range: 4.82–19.5 ug/dL), with a lack of suppression in dexamethasone tests. Here, GH1 is linked to acromegaly.