Since in osteoarthritis (OA) both cartilage and subchondral bonesuffer damages and WNT signaling pathway has a crucial role in their maintenance, the objective of the study was toanalyze expression profile of RSPO family and its receptors [leucine-rich repeat-containing G-protein coupled receptors(LGRs)] in OA tissue samples as well as in differentiating chondrocytes and osteoblasts. The gene discussed is RSPO1; the disease is osteoarthritis.