Objective. Osteoclast activation at the cartilage pannus junction is an essential step in the destruction of bone matrix in patients affected by rheumatoid arthritis (RA). Receptor activator of NFkappaB ligand (RANK-L) is responsible for osteoclast differentiation and activation. Osteoprotegerin (OPG) is an alternative, high-affinity soluble receptor for RANK-L which significantly inhibits osteoclastogenesis. Estrogens and the specific receptors α and β (ER-α and ER-α) are known to play an important role in the pathophysiology of osteoarthritis (OA). Scope of the present study is to investigate the role of ER-α and OPG gene polymorphisms in a group of women affected by RA
