The clinical diagnosis of RA is generally based on biomarkers such as the presence of the rheumatoid factor (RF), antibodies against citrullinated proteins (ACPA), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) and multi-biomarker activity (MBDA) tests (Atzeni et al., 2017). Here, PRTN3 is linked to rheumatoid arthritis.