As showed in Table 2, BAS-G, BASFI, ASDAS-ESR, and ASDAS-CRP scores and ESR and CRP levels were higher; BMD values at the femur were lower; and the prevalences of low BMD, osteopenia, and OP at the femur were higher among patients with BME on SIJ MRI than among those without BME on SIJ MRI. The gene discussed is ESR1; the disease is Osteopenia.