Steroidogenic factor 1 (SF-1) is expressed in GT, and Pit1 is expressed in tumours derived from the production lines of growth hormone (GH) (somatotroph tumours, ST), prolactin (PRL) (lactotroph tumours, LT) and thyroid-stimulating hormone (TSH) (thyrotroph tumours, TT)[7],[8]. The gene discussed is SF1; the disease is neoplasm.