The results of the association analysis between TJ protein levels and taxa abundance detected in RA patients showed a positive correlation between occludin levels and the abundance of genus rc4_4 (r = 0.241, p = 0.022) of an unknown family of order RF32 (r = 0.222, p = 0.036) and of an unknown genus of order RF32 (r = 0.222, p = 0.036). The gene discussed is OCLN; the disease is rheumatoid arthritis.