In the cross-sectional analyses, we found moderate to strong correlation between ultrasound measures such as GS and PD synovitis scores, and the following variables: TJC (r = 0.532, P <0.005 and r = 0.580, P <0.001, respectively), SJC (r = 0.684, P <0.001 and r = 0.606, P <0.001, respectively), DAS28 (r = 0.631, P <0.001 and r = 0.707, P <0.001, respectively), CRP (r = 0.451, P <0.01 and r = 0.463, P <0.005, respectively) and ESR (r = 0.376, P <0.05 and r = 0.428, P <0.01, respectively). The gene discussed is ESR1; the disease is synovitis.