TNFRSF11A and rheumatoid arthritis: Osteoclast differentiation through the RANK/RANKL/OPG system seems to be a pathwaywith implications in the regulation of bone destruction in PD patients.32 SNPs in theRANK gene have been implicated in different human diseases,including Paget's Disease, rheumatoid arthritis and osteoporosis.33,45,47