In ACPA-negative patients, osteitis and synovitis score increased significantly (1.1 to 1.7, p = 0.03, and 1.8 to 2.9, p = 0.003, respectively) during progression from arthralgia to RA, whereas tenosynovitis and erosion scores remained stable (Fig. 3). The gene discussed is PRTN3; the disease is tenosynovitis.