Paget Disease of Bone 2, Early-Onset, also known as pdb2, is related to paget's disease of bone and mammary paget's disease. An important gene associated with Paget Disease of Bone 2, Early-Onset is TNFRSF11A (TNF Receptor Superfamily Member 11a), and among its related pathways/superpathways are Clock-controlled autophagy in bone metabolism and Apoptosis and survival Anti-apoptotic TNFs/NF-kB/Bcl-2 pathway. Affiliated tissues include bone and brain, and related phenotypes are hypercalcemia and headache