Since 2017 (according with World Health Organization), they are divided into seven morphofunctional types and three lineages: somatotroph, lactotroph, and thyrotroph (PIT1 lineage), corticotroph (TPIT lineage) or gonadotroph (SF1 lineage), null cell or immunonegative tumor and plurihormonal tumors. The gene discussed is SF1; the disease is neoplasm.